The World Comes From Reason and This Reason Is a Person

A reflection on the idea that “The world comes from reason, and this reason is a Person.” (Joseph Ratzinger). The intelligibility of the world and the personal nature of the Logos.

I was recently reading Introduction to Christianity, written in 1968 by Joseph Ratzinger, later Pope Benedict XVI. One line from the introduction really stood out to me:

“The world comes from reason, and this reason is a Person.”

I think this may be the most perfect and succinct expression of what I believe. Most of the topics that interest me could be traced back to this sentence. It contains two important ideas:

1. The world is rational.

2. The world’s rationality comes from God.

That the world is rational is consistent with scientific realism, which is the view that the world described by science is real. It’s a view that I think, or at least hope, most people would agree with. Its connection to the second idea – that the world’s rationality comes from God – is not obvious. Many people believe that the world described by science is real without believing in God. Or believe in God and that the world described by science is real without connecting these two ideas. But I think these two ideas are necessarily linked. The reason the world is rational is because its rationality is God’s rationality.

Another thing I like about this statement is that it can be understood in a few ways, all of which I agree with. And the different interpretations have to do with different meanings of “come from” and “reason”, at least in this English translation of Ratzinger’s statement. That the world “comes from” reason we can understand to mean that God creat-ed (past tense) the world and that God is continually creat-ing (present tense) and sustaining the world. By “reason” we can understand “reason” as the power of the mind to think, understand, and form judgments and “reason” as a cause, explanation, or justification. Both work. So we get these four interpretations and their combinations:

“The world comes from reason”

1. At the point in time when the world came into existence it came from reason.

2. The world continues to exist in the way that it does from reason.

“And this reason is a Person”

1. Reason, as such, is a Person.

2. A Person is the reason, or cause, for the world existing.

Before digging further into this let’s look at a longer version of the quote from Ratzinger:

“The God who is logos guarantees the intelligibility of the world, the intelligibility of our existence, the aptitude of reason to know God and the reasonableness of God, even though his understanding infinitely surpasses ours and to us may so often appear to be darkness. The world comes from reason, and this reason is a Person, is Love–this is what our biblical faith tells us about God.”

The intelligibility of the world is fundamentally connected to scientific realism because it’s really what makes science possible. What are some ways in which the world is intelligible scientifically? Here are four:

1. When controlled experiments have predictable and repeatable results.

2. When the results of controlled experiments have predictable and repeatable distributions.

3. When variables in controlled experiments vary in proportion to other variables.

4. When previously unknown laws can be derived from previously known laws and confirmed by experiment. 

I include predictable and repeatable distributions because the results of experiments very often are distributions. This can either be because of variations in conditions that we can’t completely account for or because the aspect of nature itself that is being measured actually is a distribution in essence. In the first case the reason for the distribution is a limitation on our knowledge, something epistemological. In the second case the distribution is actually a property in nature itself in its essence or being, something ontological. In either case there is regularity and predictability. Even if the individual data points are not predictable their distributions are. And I think that still counts.

These four kinds of intelligibility are all basic to scientific practice. In an unintelligible world science would not be possible.

I think the novelist Cixin Liu portrayed this well in The Three Body Problem. In that novel aliens are interfering with the results of particle collider experiments to keep humans from making any progress in their scientific knowledge. One scientist describes it to a colleague using an analogy with billiard balls, a classic case of predictable physics:

“Imagine another set of results. The first time, the white ball drove the black ball into the pocket. The second time, the black ball bounced away. The third time, the black ball flew onto the ceiling. The fourth time, the black ball shot around the room like a frightened sparrow, finally taking refuge in your jacket pocket. The fifth time, the black ball flew away at nearly the speed of light, breaking the edge of the pool table, shooting through the wall, and leaving Earth and the Solar System.” (The Three Body Problem, 70)

Of course science would be impossible in that kind of world. And really we wouldn’t even get as far as attempting science because the existence of physical life depends on the regularity of matter, cellular structures, and biochemical reactions. A truly unintelligible world is difficult to imagine because it’s not the kind of world we could live in. It would be a lot like the formlessness and void, the tohu va-bohu (תֹ֙הוּ֙ וָבֹ֔הוּ) in Genesis 1:2, before God imposed order on it.

In science we are in the business of characterizing the world’s regularities. That there are such regularities in the first place we appropriately take for granted. Why and how these regularities are there in the first place is not a scientific question but a philosophical, and specifically metaphysical question. Though we can certainly be interested in that question as scientists as well. It seems like the kind of question that would not be answerable from inside the system. As a comparison, computer programs and video games also have regularities. But these come from their developers. The program has a programmer who is not part of the program. The original regularity and structure of the system comes from the outside. I understand the regularity and structure of the real world to come about in a similar way.

If the world comes from reason then what would it mean for this reason to be a person? Both that the world comes from reason and that this reason is a person are statements of faith. But there are also reasons to believe them that support that faith. That reason is a person has both philosophical and scriptural support. 

First on the philosophical support. In a previous episode I looked at the argument from eternal truths, an argument for the existence of God. In Edward Feser’s version of the argument he considers three possible versions of realism: Platonic realism, Aristotelian realism, and Scholastic realism. He describes these three possibilities in this way:

Platonic realism: abstract objects exist in a “third realm” distinct from either the material world or any intellect. 

Aristotelian realism: abstract objects exist only in human or other contingently existing intellects. 

Scholastic realism: abstract objects exist not only in contingently existing intellects but also in at least one necessarily existing intellect.

These options have some similarity to three options I’ve proposed as possible explanations for the rationality of the world:

1. The rationality of the world is independent of any intelligent beings.

2. The rationality of the world is a conditional property, conditional on there being intelligent beings in the world.

3. The rationality of the world is the rationality of a mind that grounds the world.

I think the idea of the world’s rationality being a conditional property is the most immediately plausible and straightforward, even though I think it is ultimately inadequate. It would be something of the form:

1. IF there are intelligent beings in reality.

2. AND IF any existing intelligent beings obtain some degree of accurate understanding of reality.

3. THEN such intelligent beings will find reality to be intelligible and rational.

I think that happens to be true as far as it goes. But it doesn’t explain or give grounding for the world’s intelligibility, why it is that way in the first place.

Edward Feser establishes scholastic realism, the view that abstract objects exist in at least one necessarily existing intellect, by a process of elimination; eliminating Platonic realism and Aristotelian realism for what he sees as insuperable objections. I won’t go into the insuperable objections to Platonic realism and Aristotelian realism here but just refer those interested to Feser’s text, and move on now to the scriptural foundation for seeing reason as a person.

First, what is the alternative to a personal nature? It would be an impersonal nature. For example, in the times of classical Greece and the Roman Empire the stoics and other educated people understood the world to be governed by logos (λόγος).  Heraclitus (535 – 475 BC) said all things come to pass in accordance with the logos (γινομένων γὰρ πάντων κατὰ τὸν λόγον, ginomenon gar panton kata ton logon). The Stoics had a concept of logos spermatikos (λόγος σπερματικός), understood as the generative principle of the world that creates all things. Very similar to Ratzinger’s statement that the world comes from reason. But an important difference was that the Greeks and Romans did not understand the logos to be personal, but impersonal; law without a lawgiver. What then are we to understand from the following Biblical passage?:

“In the beginning was the Word (Λόγος), and the Word was with God, and the Word was God. The same was in the beginning with God. All things were made by him; and without him was not any thing made that was made.” (John 1:3, KJV)

From this passage alone, in the prologue to John’s gospel, we might still understand the Logos to be an impersonal, generative power. Both share a common principle that it is by the Logos that all things are made. But the Gospel writer then makes clear that this Logos is not impersonal at all and actually became, of all things, a human being:

“And the Word was made flesh, and dwelt among us.” (John 1:14, KJV)

The Logos was made flesh, the man Jesus of Nazareth. This Incarnation allowed other human beings to see and know God. Up to that point man had seen no form in God, as had been made reiterated to the Israelites in the Torah:

“Take careful heed to yourselves, for you saw no form when the Lord spoke to you at Horeb out of the midst of the fire, lest you act corruptly and make for yourselves a carved image in the form of any figure: the likeness of male or female” (Deuteronomy 4:15-16, NKJV)

John acknowledges that this had been the case. But with the Incarnation of Jesus things change.

“And we beheld his glory, the glory as of the only begotten of the Father, full of grace and truth.” (John 1:14, KJV)

“No man hath seen God at any time, the only begotten Son, which is in the bosom of the Father, he hath declared him.” (John 1:18, KJV)

Jesus then could rightfully say:

“He that hath seen me hath seen the Father” (John 14:9, KJV)

Not that they are the same person. That would be a misunderstanding of the Trinity, “confounding the persons”. But in Jesus of Nazareth human beings could see God in the flesh, as a fellow human being and as a person.

As a person God has a mind, a will, self-consciousness, and awareness. What’s more God has all these things in greater and in more perfect measure than we do. We are created in God’s image. So these personal attributes as we find them in ourselves are patterned after their more perfect form in God’s personal attributes.

Thomas Aquinas (1225-1274) described this well in his Summa Theologiae:

“‘Person’ signifies what is most perfect in all nature—that is, a subsistent individual of a rational nature. Hence, since everything that is perfect must be attributed to God, forasmuch as His essence contains every perfection, this name ‘person’ is fittingly applied to God; not, however, as it is applied to creatures, but in a more excellent way; as other names also, which, while giving them to creatures, we attribute to God… Although the word ‘person’ is not found applied to God in Scripture, either in the Old or New Testament, nevertheless what the word signifies is found to be affirmed of God in many places of Scripture; as that He is the supreme self-subsisting being, and the most perfectly intelligent being.” (Summa Theologiae 1.29.3)

What’s the upshot of that? Here’s how I think about it. Do we really matter? We certainly matter to each other. But we’re not always fair to each other. And we’re not in control of the world so we’re limited in how much we can actually do for each other. If the world comes from an impersonal source that source is indifferent to us. Whether we live or die, thrive or suffer. But if the world comes from a person we can matter to him. And the witness of scripture is that we do. We matter to God and God is powerful over all other forces. Paul’s message in Romans 8:31-39 is spot on:

“What then shall we say to these things? If God is for us, who can be against us? He who did not spare His own Son, but delivered Him up for us all, how shall He not with Him also freely give us all things? Who shall bring a charge against God’s elect? It is God who justifies. Who is he who condemns? It is Christ who died, and furthermore is also risen, who is even at the right hand of God, who also makes intercession for us. Who shall separate us from the love of Christ? Shall tribulation, or distress, or persecution, or famine, or nakedness, or peril, or sword? As it is written: ‘For Your sake we are killed all day long; We are accounted as sheep for the slaughter.’ Yet in all these things we are more than conquerors through Him who loved us. For I am persuaded that neither death nor life, nor angels nor principalities nor powers, nor things present nor things to come, nor height nor depth, nor any other created thing, shall be able to separate us from the love of God which is in Christ Jesus our Lord.”

The Existence of God: Argument from Eternal Truths

I think that there are certain ideas – like in mathematics and logic – that are necessarily true in a way that is separate from space, time, and material things. Such ideas must exist in a way that is very different from material things. We could suppose that these ideas are products of our minds; and there does seem to be something mental about them. But these ideas also seem to have real effects in the material world. All matter in the universe behaves in consistently mathematical ways that don’t depend on our minds. Still, I think we’re right to understand these ideas as mental. They just have to be features of a very different kind of mind, a mind that is eternal and that has effects on all the matter in the universe.

Theology, as the study of God and the things of God, naturally takes the existence of God as a first principle. When studying other theological topics like God’s nature, humanity, and salvation we take God’s existence for granted. And in our own religious development many of us concern ourselves with these other topics before concerning ourselves with the existence of God. Especially in times when belief in God was more universal, people probably worried more about salvation from their sins and how to get right with God, whose existence they took for granted. Still, in systematic theology, where we’re considering the logical relations between ideas it makes sense to start with God’s existence.

Why do people believe in God? I’ve actually asked a lot of people why they believe in God and in most cases the people I’ve talked to don’t believe in God for intellectual reasons. Some have had spiritual experiences that lead them to believe. Some are led to believe because they take seriously the issues of life’s purpose, death, pain, and the need for meaning; what I call existential issues. I think those are good reasons to believe in God. I share those reasons. But I think in my own life intellectual reasons have actually come first, with spiritual and existential reasons coming after. Maybe that’s unusual but that’s just how it’s happened. So that’s what I want to focus on presently; not because intellectual reasons are the most important, but because they’re the most natural for me. And because they lay out the first principles for the rest of systematic theology as a rational structure.

Intellectual reasons for believing in God are expressed most formally as arguments. Arguments here in the technical sense, not in the sense of being ornery and quarrelsome. An argument is a group of statements put together to show that certain statements provide reasons to believe another statement. These different statements are premises and conclusions. An argument is put together to show how certain premises provide reasons to believe a certain conclusion. There are many arguments for the existence of God. By the nature of what an argument is then this means that there are reasons to believe in God. It doesn’t mean that they are automatically good reasons, but there are reasons.

Valid deductive arguments are understood to follow absolutely from their premises. If an argument is deductively valid the conclusion cannot fail to follow from its premises. If the premises are true the conclusion must be true. This means then that a lot of discussion about arguments focuses on the premises. There are definitely deductively valid arguments for the existence of God. But it’s obviously still possible to reject these arguments, not because the conclusions don’t follow from the premises – they do – but because not everyone accepts the premises of the arguments. There’s no argument for the existence of God that seals the deal and convinces everyone. But there are arguments that I find convincing.

The most prominent arguments for the existence of God are:

– The Cosmological Argument

– The Teleological Argument

– The Moral Argument

– The Ontological Argument

I think the cosmological, teleological, and moral arguments are all very good arguments and I find them convincing. I’m not sure about the ontological argument. I think it’s either untenable or absolutely brilliant. But I don’t grasp it well enough to know yet. Regardless, I’m actually not going to talk about any of these arguments any more right now because they aren’t the most compelling for me personally. Instead I want to focus presently on an argument that I personally find the most compelling and interesting:

– The Argument from Eternal Truths

This argument is not as well known and it’s not an easy argument to understand. So I’d like to present it in stages of increasing detail, starting with a short version of just a few sentences and moving toward a longer, more formal version. It was actually the short version that I’ve put the most effort into. For one thing, with the longer, more formal versions I’ve relied on the work of others. And even though I understood their expressions of the argument and found them persuasive I didn’t find them succinct enough to share with people. It can be quite difficult to refine longer arguments into short statements. It necessarily eliminates supporting details and you have to just let that go.

My own version is not an argument in the technical sense but an informal explanation. Here’s the short version:

I think that there are certain ideas that are true in a way that is separate from space, time, and material things. We could suppose that these ideas are products of our minds; and there does seem to be something mental about them. But they would have to be features of a very different kind of mind, a mind that is eternal and that has effects on all the matter in the universe.

That’s the gist, as best as I can think to put it this briefly. That is, informally, an explanation for why I believe in God intellectually. Three key components here to point out:

1. Ideas

2. Mind

3. Eternity

The ideas in question here are things like mathematical truths, logical truths, laws of physics and chemistry; things that are true anywhere and everywhere, all the time. Here’s a slightly longer version of the above statement that adds some of this detail:

I think that there are certain ideas – like in mathematics and logic – that are necessarily true in a way that is separate from space, time, and material things. Such ideas must exist in a way that is very different from material things. We could suppose that these ideas are products of our minds; and there does seem to be something mental about them. But these ideas also seem to have real effects in the material world. All matter in the universe behaves in consistently mathematical ways that don’t depend on our minds. Still, I think we’re right to understand these ideas as mental. They just have to be features of a very different kind of mind, a mind that is eternal and that has effects on all the matter in the universe.

I think I find this kind of explanation compelling because of my background working in chemistry and materials science. I spend a lot of time thinking about matter and the way it behaves, the patterns in the behavior of matter. So I’m especially inclined to think about what governs matter. Versions of the argument from eternal truths that I’ll talk about subsequently focus on different aspects but I think they get at much the same core principles.

The classical statement of the argument from eternal truths comes from Augustine of Hippo (354 – 430) in his book On Free Choice of the Will. In Book II he gives the argument from eternal truths in the form of a dialogue with a character named Evodius. He uses mathematics as an example of eternal truths:

“The intelligible structure [ratio] and truth of number is present to all reasoning beings. Everyone who calculates tries to apprehend it with his own reason and intelligence.” (

And he stresses that such truths are eternal, i.e. valid at all times:

“I do not know how long anything I touch with the bodily senses will last, for example when I sense the Earth or the sky or any physical objects in them. But seven and three are ten not only at the moment, but always; it never was and never will be the case that seven and three are not ten. I therefore declared that this incorruptible numerical truth is common to me and to any reasoning being.” (

Later he proposes three options:

“Then, in regard to this truth we have long been talking about and in which we recognize so many things: Do you think it is (a) more excellent than our mind is, (b) equal to our minds, or even (c) inferior?” (

The option that these truths are inferior to our minds would be the idea that they are wholly products or our creation. This would be a very strong form of social constructionism. Augustine doesn’t accept this option:

“When anyone says that eternal things are more valuable than temporal things, or seven and three are ten, no one says that it ought to be so; he simply knows that it is so. He is not an inspector making corrections but merely a discoverer taking delight.” (

The second option is that truths are equal to our minds. This is a weaker form of social constructionism and I think is more commonly held. Truths aren’t just arbitrary but they’re still essentially dependent on our minds. Truths are products of our mind’s ways of constructing a mental picture of the world, of our mental “categories”. But Augustine objects to this on account of our mind’s changeability:

“Now if (b) were the case, that this truth is equal to our minds, then it would itself be changeable. For our minds sometimes see more of the truth and sometimes less. And for this reason, they acknowledge themselves to be changeable. The truth, remaining in itself, neither increases when we see more of it nor decreases when we see less, but instead it is intact and uncorrupted, bringing joy with its light to those who turn towards it and punishing with blindness those who turn away from it.” (

Another way he might have said this is that three and seven would make ten even if no one in the world believed it, or even if there were no people at all. There are certainly arguments to the contrary, some of which will be addressed later, but I think this conforms pretty well to the way most people think about truth.

Another example would be truths of advanced mathematics, which are much more complicated and the question of whether they were true before they were discovered or only became true when they were first expressed. Roger Penrose refers to the example of the Mandelbrot set:

“The particular swirls of the Mandelbrot set… did not attain their existence at the moment that they were first seen on a computer screen or printout. Nor did they come about when the general idea behind the Mandelbrot set was first humanly put forth… Those designs were already ‘in existence’ since the beginning of time, in the potential timeless sense that they would necessarily be revealed precisely in the form that we perceive them today, no matter at what time or in what location some perceiving being might have chosen to examine them.” (Penose, The Road to Reality, 17)

Augustine thought similarly and from this he concluded that the truths must be more excellent than our minds:

“Consequently, if the truth is neither inferior nor equal, it follows that it is superior and more excellent. Now I had promised you, if you recall, that I would show you that there is something more exalted than our mind and reason. Here you have it: the truth itself!” (

Augustine then identifies that which is superior to our minds and reason as God. This is the classical formulation of the argument from eternal forms. I think it does a good job of laying out all the essential ideas. Some of the more modern versions that follow I think improve on it and make the argument more formal.

One modern version of the argument is given by Lorraine Juliano Keller in her 2018 paper “The Argument from Intentionality (or Aboutness): Propositions Supernaturalized”. In that paper she gives a few versions of the argument. First she gives this informal expression of the “rough idea”:

“Truth involves representation–something is true only if it represents reality as being a certain way, and reality is that way. But representation is a function of minds. So, truth is mind-dependent. Yet there are truths that transcend the human mind, e.g. eternal truths. So, there must be a supreme mind with the representational capacity to “think” these transcendent truths. Therefore, a supreme mind (viz., God) exists.” (Dougherty, Wallis, Two Dozen (or so) Arguments for God: The Plantinga Project, 11)

One important thing to point out here is how Keller juxtaposes two ideas that are in tension and then synthesizes them together. The two ideas are:

1. Truth is a product of mind

2. Truths are independent of our minds

The second idea, that truths are independent of our minds, is one I very much want to endorse. But the first idea, that truth is a product of mind also seems right. As I said in my own explanation, there does seem to be something mental about true ideas. Keller links truth with representation. What does that mean? I think Richard Rorty gave a good explanation of this:

“We need to make a distinction between the claim that the world is out there and the claim that truth is out there. To say that the world is out there, that it is not our creation, is to say, with common sense, that most things in space and time are the effects of causes which do not include human mental states. To say that truth is not out there is simply to say that where there are no sentences there is no truth, that sentences are elements of human languages, and that human languages are human creations. Truth cannot be out there – cannot exist independently of the human mind – because sentences cannot so exist, or be out there. The world is out there, but descriptions of the world are not. Only descriptions of the world can be true or false. The world on its own – unaided by the describing activities of human beings – cannot.” (Rorty, Contingency, Irony, and Solidarity)

I don’t agree with Rorty’s statement in its entirety but I think there’s a lot here that he does get right and it supports Keller’s point about truth involving representation. Rorty says that, “Where there are no sentences there is no truth.” Let’s grant that. He also says that, “sentences are elements of human languages, and that human languages are human creations.” Here’s where I disagree. And I think this difference is key. Recall the two key ideas I picked out in Keller’s statement above:

1. Truth is a product of mind

2. Truths are independent of our minds

Are these two ideas contradictory? No, actually. They’re in tension certainly. And Rorty picks up on that. But note that Rorty points to human languages and human creations. But things change significantly if we do not so restrict ourselves. We can say both that (1) truth is a product of mind but also that (2) truths are independent of our minds, of human minds. We can do that if we also consider other minds, or another mind. The mind of God.

With all that in mind let’s now look at her formal expression of the argument:

1. Propositions represent essentially [Premise]

2. Only agents represent fundamentally [Premise]

3. So propositions depend for their existence on agents. [from 1,2]

4. There are propositions that no finite agent entertains (transcendent propositions).

5. The representation of transcendent propositions is independent of the representation of finite agents. [from 4]

6. So, transcendent propositions cannot depend on finite agents. [from 3,5]

7. Therefore, there’s an infinite agent.

Hopefully this is clear enough in light of all the foregoing. The argument starts with the nature of propositions and the nature of representation. Propositions are representational in nature, like Rorty insisted. And only agents can represent. Nevertheless there are propositions that no humans are representing: talking about or thinking about. So who is thinking these propositions? Rorty denies that such propositions would exist at all. But I’m rejecting that idea. If propositions exist even when no human being is thinking them someone else has to be thinking them. Furthermore these propositions are transcendent and eternal. They can only exist in that way if they are thought by an infinite thinking agent.

I think this is a good argument. There are two main ways to get around it.

1. Deny that propositions represent essentially

2. Deny that there are transcendent propositions, propositions that no finite agent entertains

I’ll address the first denial in the next argument from Edward Feser. Alternatives to this premise include Platonism and Aristotelianism.

The second denial is a very big topic that I won’t go into here in detail. But I’ll touch on it. It’s a debate about universals, a debate going back to at least the Middle Ages in Europe and in other forms before that. The two major positions are realism and nominalism. With the example of mathematics two positions are mathematical realism and mathematical anti-realism, the basic question there being whether mathematical truths are things we discover or create.

I’m a mathematical realist but there are some important clarifications necessary to make this positions sufficiently sophisticated. The issue that complicates things is that there are many different mathematical systems we can work in and they have different rules. For example in Euclidean geometry parallel lines never converge or diverge. But we can change the rules to make different geometries to allow parallel lines to converge (elliptic geometry) or diverge (hyperbolic geometry). That sure makes it seem like we are free to invent mathematics in any way we like. But is that the case? No, I don’t think so. Because in whatever geometry we choose we are still constrained by the conditions of that geometry.

I think Alex Kontorovich put it well when he said: “The questions that are being asked are an invention. The answers are a discovery.” Having said that, I think it’s also important that any questions we ask be well-formed. For example, you can’t just ask the question, “Is it green?” and expect for there to be a right answer without specifying what “it” is. But as you set conditions to your system it shapes its structure for certain right and wrong answers that are not arbitrary.

As another example of this principle, I’m reading an excellent book that just came out this year (2022) by Eugenia Cheng called The Joy of Abstraction. It’s a book about a general theory of mathematical structures called category theory. I highly recommend it. Early in the book she addresses the issue of whether a proposition like “2+2=4” is absolutely true. She gives the example of modular arithmetic in which this may or may not be true. For example in modulus 3 2+2=1. Or another, more practical every-day example, in modulus 12 (like with a clock) 5+9=2 (5 PM plus 9 hours is 2 AM). So, she maintains, mathematics is different in different contexts:

“Mathematical objects behave very differently in different contexts; thus they have no fixed characteristics, just different characteristics in different contexts. The truth is not absolute but is contextual, and so we should always be clear about the context we’re considering… Pedantically one might declare that the ‘truth-in-context’ is then absolute, but I think this amounts to saying that truth is relative to context. Your preferred wording is a matter of choice, but I have made my choice because I think it is important to focus our attention on the context in which we are working, and not regard anything as fixed.” (Cheng, 44)

I have no disagreement with that; other than being called “pedantic”, but that’s OK. I’ll take that allowance that our preferred wording is a matter of choice. And I actually think that for purposes of category theory Cheng’s preference makes sense. But for my present purposes I prefer the other option, that “truth-in-context” is absolute.

That’s all I’ll say for now about realism for universals. It’s a big topic. But those are some of my reasons for thinking the way I do around it. And I think they’re reasonable.

The last version of the argument from eternal truths I want to share is from Edward Feser in his 2017 book Five Proofs of the Existence of God. His third proof he calls the “the Augustinian Proof”, as a nod to Augustine’s exposition of it in On Free Choice of the Will. Feser summarizes it in this way:

“It begins by arguing that universals (redness, humanness, triangularity, etc.), propositions, possibilities, and other abstract objects are in some sense real, but rejects Plato’s conception of such objects as existing in a “third realm” distinct from any mind and distinct from the world of particular things. The only possible ultimate ground of these objects, the argument concludes, is a divine intellect—the mind of God.” (Feser, 13)

It’s the same general set of ideas and structure as we’ve seen in the other versions. In his chapter on this proof he gives a formal version of the argument in 29 statements. I like this argument because it’s very thorough. But it’s also very long so it is harder to follow. But I think having looked at the earlier versions of the argument it will help. Let’s go ahead and go through all 29 statements of Feser’s argument and then comment on certain parts of it.

1. There are three possible accounts of abstract objects such as universals, propositions, numbers and other mathematical objects, and possible worlds: realism, nominalism, and conceptualism. 

2. There are decisive arguments in favor of realism. 

3. There are insuperable objections against nominalism. 

4. There are insuperable objections against conceptualism. 

5. So, some version of realism is true. 

6. There are three possible versions of realism: Platonic realism, Aristotelian realism, and Scholastic realism. 

7. If Platonic realism is true, then abstract objects exist in a “third realm” distinct from either the material world or any intellect. 

8. If Aristotelian realism is true, then abstract objects exist only in human or other contingently existing intellects. 

9. If Scholastic realism is true, then abstract objects exist not only in contingently existing intellects but also in at least one necessarily existing intellect. 

10. There are insuperable objections against the claim that abstract objects exist in a “third realm” distinct from either the material world or any intellect. 

11. So, Platonic realism is not true. 

12. There are insuperable objections against the claim that abstract objects exist only in human or other contingently existing intellects. 

13. So, Aristotelian realism is not true. 

14. So, Scholastic realism is true. 

15. So, abstract objects exist not only in contingently existing intellects but also in at least one necessarily existing intellect. 

16. Abstract objects such as universals, propositions, numbers and other mathematical objects, and possible worlds are all logically related to one another in such a way that they form an interlocking system of ideas. 

17. The reasons for concluding that at least some abstract objects exist in a necessarily existing intellect also entail that this interlocking system of ideas must exist in a necessarily existing intellect. 

18. So, this interlocking system of ideas exists in at least one necessarily existing intellect. 

19. A necessarily existing intellect would be purely actual. 

20. There cannot be more than one thing that is purely actual. 

21. So, there cannot be more than one necessarily existing intellect. 

22. An intellect in which the interlocking system of ideas in question existed would be conceptually omniscient. 

23. So, the one necessarily existing intellect is conceptually omniscient. 

24. If this one necessarily existing intellect were not also omniscient in the stronger sense that it knows all contingent truths, then it would have unrealized potential and thus not be purely actual. 

25. So, it is also omniscient in this stronger sense. 

26. What is purely actual must also be omnipotent, fully good, immutable, immaterial, incorporeal, and eternal. 

27. So, there is exactly one necessarily existing intellect, which is purely actual, omniscient, omnipotent, fully good, immutable, immaterial, incorporeal, and eternal. 

28. But for there to be such a thing is just what it is for God to exist. 

29. So, God exists.

See Feser, pages 109 – 110

The first part of the argument concerns the nature of eternal truths, what he calls abstract objects. How to account for them? And he proposes three options: realism, nominalism, and conceptualism. We’ve talked about this before and why I think realism is the best option. Realism is the view that abstract objects “are real, and neither reducible to anything material nor sheer constructs of the human mind”. Nominalism “denies that abstract objects are real”. Conceptualism “allows that they are real but insists that they are wholly constructed by the human mind”. (90)

Feser gives 10 arguments in favor of realism, which I won’t go over here but just list. You can either read about them further in his book or just look them up online. His 10 arguments in favor of realism are:

– The “one over many” argument

– The argument from geometry

– The argument from mathematics in general

– The argument from the nature of propositions

– The argument from science

– The argument from the nature of possible worlds

– The vicious regress problem

– The “words are universals too” problem

– The argument from the objectivity of concepts and knowledge

– The argument from the incoherence of psychologism

Some of these have already been touched on. I’ll just say a little more about the argument from science because I find that one especially interesting personally. Feser says:

“Scientific laws and classifications, being general or universal in their application, necessarily make reference to universals; and science is in the business of discovering objective, mind-independent facts. Hence, to accept the results of science is to accept that there are universals that do not depend for their existence on the human mind. Science also makes use of mathematical formulations, and since (as noted above) mathematics concerns a realm of abstract objects, to accept the results of science thus commits one to accepting that there are such abstract objects.” (92)

I touched on this earlier talking about how eternal truths seem to have real effects in the material world, that all matter in the universe behaves in consistently mathematical ways, that don’t depend on our minds. Eugene Wigner called this “The Unreasonable Effectiveness of Mathematics in the Natural Sciences”. Though I would call it the remarkable effectiveness of mathematics in the natural sciences, because I don’t think it’s unreasonable, rather, divine reason is precisely what is behind it.

After having argued for realism about universals in the next part of the argument Feser touches on the nature of such universals. In what way do these universals exist? He proposes three options: Platonic realism, Aristotelian realism, and Scholastic realism.

Under Platonic realism abstract objects don’t exist in the material world nor in the human mind “but in a ‘third realm’ that is neither material nor mental” (97). 

“This is the famous realm of Platonic Forms, entities which exist outside time and space and which the things of our experience merely imperfectly ‘resemble’ or ‘participate’ in.” (97)

In many ways I consider myself a Platonist. Or at least, I think there’s a lot that Platonism gets right. But I don’t go quite all the way with Platonism for various reasons. One of these reasons is that I’ve been persuaded that abstract objects are mental in a way that Platonic Forms are not. 

Feser mentions three problems with Platonism. First, the Forms seem to be causally inert. Since one of the reasons for thinking that realism is true in the first place is the remarkable effectiveness of mathematics in the natural sciences this would be a problem, because things that are causally inert can hardly be effective. The second problem is the “Third Man” argument, which I won’t go into but has to do with an infinite regress of meta-forms. The third problem is that it’s not clear with the notion of material objects resembling the Forms that an object is more a genuine instance of itself than an image of it would be, for example a human person a more genuine person than a statue of a human. For more detail on all this just see his book.

Under Aristotelian realism universals do not exist in a “third realm” of Forms but in particular objects. The universals are features that we abstract from concrete individual objects. The universals really do exist but are instantiated in individual objects, rather than in a “third realm” of Forms. Feser describes it this way:

“The universals are abstracted from these [particular objects] extramental things by the mind, rather than being the free creations of the mind. Aristotelian realists emphasize that abstraction is essentially a mental process, so that abstract objects are essentially tied to the mind. Hence, though animality, triangularity, redness, humanness, and so forth do exist in mind-independent reality, they do not exist there as abstract objects, but only as tied to concrete particular individuals. And though animality, triangularity, redness, humanness, and so forth can nevertheless exist as abstract objects, they do not so exist in mind-independent reality. There is no third Platonic alternative way for universals to exist—namely, as both abstract and mind-independent at the same time.” (100)

The problems with Aristotelian realism that Feser points out concern its dependence on the material world. What if the material world didn’t exist at all. This would seem to be an at-least-possible counterfactual. How would Aristotelian realism obtain in that case? How would a material world or human minds come into existence? There wouldn’t seem to be any grounding for that possibility since Aristotelian realism would require something material already present to ground it. Other counterfactuals present problems. There are plenty of things that could have existed but haven’t come into existence. Daniel Dennett has talked about the “Library of Mendel”, a theoretical library containing all possible genomes (Darwin’s Dangerous Idea). There would seem to be an infinite number of potential organisms that have never come into material existence. But if these potential organisms have never actually come into existence there couldn’t be any place for their forms to be physically instantiated in Aristotelian realism. But it doesn’t seem like they are any less logically possible for that fact. Finally, there would seem to be propositions “that would be true whether or not the material world or any human mind existed.” (101) But if the material world didn’t exist there would be no grounding for these propositions in Aristotelian realism. Same for necessary truths of mathematics and logic. So Feser rejects Aristoelian realism.

The remaining option to account for realism is Scholastic realism. Feser describes it this way:

“This brings us, at last, to Scholastic realism, which is essentially Aristotelian in spirit, but gives at least a nod to Platonic realism. Like Aristotelian realism, Scholastic realism affirms that universals exist only either in the things that instantiate them, or in intellects which entertain them. It agrees that there is no Platonic “third realm” independent both of the material world and of all intellects. However, the Scholastic realist agrees with the Platonist that there must be some realm distinct both from the material world and from human and other finite intellects. In particular—and endorsing a thesis famously associated with Saint Augustine—it holds that universals, propositions, mathematical and logical truths, and necessities and possibilities exist in an infinite, eternal, divine intellect. If some form of realism must be true, then, but Platonic realism and Aristotelian realism are in various ways inadequate, then the only remaining version, Scholastic realism, must be correct. And since Scholastic realism entails that there is an infinite divine intellect, then there really must be such an intellect. In other words, God exists.” (102)

The remaining fifteen statements in Feser’s argument follow from Scholastic realism, working out the attributes that this necessarily existing intellect must have. For example, that there can only be one such intellect and that he must be omniscient and omnipotent. I think these three are related in a rather interesting way.

One reason for holding realism to be true in the first place is the observation that matter behaves according to patterns of eternal truths, for example the mathematical forms of the laws of physics. For this to occur it’s not sufficient just that these eternal truths be thought. These thoughts must also have causal power. The mind that thinks these eternal truths must also be causing them to have the effects that they have in the material world. One way of talking about this causality is in terms of actuality and potentiality.

Fair warning: the next couple minutes might be a little hard to follow because it gets into some technical jargon from classical and medieval philosophy. If it’s too much just hold tight for a few minutes.

Actuality and potentiality are ideas from Aristotle that also feature prominently in the philosophy of Thomas Aquinas. Potentiality is any possibility that a thing has. Actuality is what causes a thing’s potentiality to be realized. In Aristotle’s philosophy these concepts equipped him to give an account for change and rebut arguments against the possibility of change by philosophers like Parmendies. Change is “the actualization of a potential” (Feser, 18). Everything in the universe has multiple ways that they can be. At any given moment things are a certain way. But they can be otherwise. They have unrealized potentiality. In order for a thing to change and realize different potentialities something must cause that change. What causes these changes are actualities.

One statement in Feser’s argument is that a necessary being is purely actual. Why must that be? This is important and it connects the related attributes of oneness, omniscience, and omnipotence. A necessary being is one who cannot fail to exist. He has always existed and always will exist. Furthermore, he was never created in the first place. He is the one who creates but is himself uncreated. In the terms just described earlier, he has no potentiality that is actualized by something else. He is not brought into existence by anything else. He is what actualizes the potentialities of everything else. Lacking any potentiality he is pure actuality.

Another statement in Feser’s argument is that there cannot be more than one thing that is purely actual. Why is that? There are a number of reasons. One reason is that the sum of all knowledge consists of an interlocking system of ideas that is indivisible. More on that shortly. Another reason is the following:

“In order for there to be more than one purely actual actualizer, there would have to be some differentiating feature that one such actualizer has that the other lack. But there could be such a differentiating feature only if a purely actual actualizer had some unactualized potential, which being purely actual, it does not have. So, there can be no such differentiating feature, and thus no way for there to be more than one purely actual actualizer.” (36)

So the unity, the oneness of the necessarily existing intellect follows from its pure actuality.

Another statement in Feser’s argument is that what is purely actual must be omnipotent. I think it’s actually pretty straightforward to see that actuality entails power. Actuality is what brings about change; actualizing potentialities. The necessarily existing intellect is purely actual and the only thing that is purely actual. Everything else has potentiality that must be actualized by something else. Eventually this all ties back to the one purely actual necessarily existing intellect. As Feser states:

“To have power entails being able to actualize potentials. Any potential that is actualized is either actualized by the purely actual actualizer or by a series of actualizers which terminates in the purely actual actualizer. So, all power derives from the purely actual actualizer. But to be that from which all power derives is to be omnipotent. So, the purely actual actualizer is omnipotent.” (37)

Finally omniscience. This is closely connected to the fact that there is only one necessarily existing intellect. Recall that it is in the mind of this one necessarily existing intellect that abstract objects such as universals, propositions, numbers and other mathematical objects, and possible worlds reside. Since there is only one necessarily existing intellect it’s not as if “such-and-such possible worlds, necessary truths, universals, and so forth exist in necessarily existing intellect A, and another group of possible worlds, necessary truths, universals, and so forth exist in necessarily existing intellect B.” (104) This wouldn’t really work anyway by virtue of the nature of abstract objects. Abstract objects “are not independent of one another in a way that would allow their ultimate ground to lie in distinct necessarily existing minds. Rather, they form an interlocking system.” (104) It all exists in only one necessarily existing intellect. This one knows all these things, all universals, propositions, numbers and other mathematical objects, and possible worlds. The one necessarily existing intellect knows all these things.

This knowledge is certainly unfathomably vast. Is there anything that it doesn’t include? Is there anything that this one intellect would not know? He knows all universals, propositions, numbers and other mathematical objects, and possible worlds. But what about contingent truths, like the fact that I went to the grocery store at 8 PM this evening? Here too actuality is key. On this Feser states the following:

“It would also have to know all truths, including contingent ones. For if it knew less than all of them, then it would have an unactualized potential–the potential to know the truths that it does not in fact know–and thus fail to be purely actual. So, it must be omniscient in an unqualified sense.” (106)

So we have one intellect who is both omniscient and omnipotent. It’s a long argument and it takes some effort to stick with it, work all the way through it, and really understand each step in the argument. But I think it’s worth it. It’s a good argument and the most detailed of the ones presented here.

People come at arguments with different inclinations to find different premises more or less plausible. I don’t expect that if I find a certain argument persuasive that everyone will find it persuasive, because they may not come to it as open to the premises of the argument as I am. And it’s certainly the case with me and arguments that I don’t find persuasive. An argument that one person finds persuasive I may not find persuasive at all because the premises don’t seem as plausible to me. And if we want to pursue the argument further we have to dig deeper into the premises. And so it goes.

In my case I really do find these arguments from eternal truths quite persuasive. I think it’s natural to suspect arguments for the existence of God to be motivated reasoning. We already believe in God for non-rational reasons so let’s try to come up with some rational explanation to make a case for what we already believe. First thing to say there is that I actually don’t think such rational reconstruction is illegitimate anyway. We believe a lot of correct things first for non-rational reasons and then only work out the rational justification for it after the fact. That’s perfectly fine. But also in my case I actually do just happen to find this to be the most plausible account for the way things are. Not just about God, but about everything, especially in the sciences. 

The deeper I look into the nature of things the more I see reality not as mere matter but as intellectually structured. As Joseph Ratzinger put it: “The intellectual structure that being possesses and that we can re-think is the expression of a creative premeditation, to which they owe their existence.” (Introduction to Christianity, 152) When everywhere I look I find more and more rational, intellectual structure, what else can I think? I’m practically compelled and driven to these conclusions.

We’ve gone over a lot here so having passed through all this I’d like to finish by returning to the simplified, shorter expressions of the ideas involved here. I’ll share the summaries of Feser and Keller and then finish with my own.


“It begins by arguing that universals (redness, humanness, triangularity, etc.), propositions, possibilities, and other abstract objects are in some sense real, but rejects Plato’s conception of such objects as existing in a “third realm” distinct from any mind and distinct from the world of particular things. The only possible ultimate ground of these objects, the argument concludes, is a divine intellect—the mind of God.” (Feser, 13)


“Truth involves representation–something is true only if it represents reality as being a certain way, and reality is that way. But representation is a function of minds. So, truth is mind-dependent. Yet there are truths that transcend the human mind, e.g. eternal truths. So, there must be a supreme mind with the representational capacity to ‘think’ these transcendent truths. Therefore, a supreme mind (viz., God) exists.” (Dougherty, Wallis, Two Dozen (or so) Arguments for God: The Plantinga Project, 11)

And mine:

I think that there are certain ideas – like in mathematics and logic – that are necessarily true in a way that is separate from space, time, and material things. Such ideas must exist in a way that is very different from material things. We could suppose that these ideas are products of our minds; and there does seem to be something mental about them. But these ideas also seem to have real effects in the material world. All matter in the universe behaves in consistently mathematical ways that don’t depend on our minds. Still, I think we’re right to understand these ideas as mental. They just have to be features of a very different kind of mind, a mind that is eternal and that has effects on all the matter in the universe.

Systematic Theology: Ethics

The statutes and judgments given to Israel were a mark of their special wisdom and understanding: “Surely this great nation is a wise and understanding people.” (Deuteronomy 4:6) Such wisdom and understanding are valuable to us not only for understanding the way things are but also for knowing how to live. The laws and statutes given by God are worth continual study and bring great reward: “O how I love thy law! It is my meditation all the day.” (Psalm 119:97)

The history of the world is punctuated with certain transformative events that have fundamentally altered its course. The most significant of such events was the mortal life of Jesus of Nazareth. At the completion of that event, with the Resurrection of Christ, everything changed. The most salient fact of human existence, our finite temporal horizon ending with death, was abolished. Another transformative event took place about one thousand years before that in the wilderness of Sinai, when Moses received the torah (תּוֹרָה) “instruction”, at the hand of the Lord. This too was a foundational event in the history of the world on which the legal, moral, and philosophical developments of the nations have turned in the centuries since. Moses himself witnessed to the people that this would be the case and called their attention to it in his great recitation in Deuteronomy: 

“Surely I have taught you statutes and judgments, just as the Lord my God commanded me, that you should act according to them in the land which you go to possess. Therefore be careful to observe them; for this is your wisdom and your understanding in the sight of the peoples who will hear all these statutes, and say, ‘Surely this great nation is a wise and understanding people.’ For what great nation is there that has God so near to it, as the Lord our God is to us, for whatever reason we may call upon Him? And what great nation is there that has such statutes and righteous judgments as are in all this law which I set before you this day? (Deuteronomy 4:5-8, NKJV) 

The statutes and judgments distinguish Israel and make it noteworthy among the nations. “Surely this great nation is a wise and understanding people.” Considering how many nations and peoples look to the Bible, to the statutes and judgments that the Lord gave to Israel, it seems to me that this has been dramatically fulfilled in the centuries following Sinai. 

I find the torah a joy to read: a rich source of inspiration for the mind and for the practical aspects of life, both theory and wisdom. I recently read a Psalm that seemed like a perfect response to the Lord’s divine instruction. 

“O how I love thy law! it is my meditation all the day.
Thou through thy commandments hast made me wiser than mine enemies: for they are ever with me.
I have more understanding than all my teachers: for thy testimonies are my meditation.
I understand more than the ancients, because I keep thy precepts.
I have refrained my feet from every evil way, that I might keep thy word.
I have not departed from thy judgments: for thou hast taught me.
How sweet are thy words unto my taste! yea, sweeter than honey to my mouth!
Through thy precepts I get understanding: therefore I hate every false way.”
(Psalm 119:97-104, KJV) 

What kind of person do you want to be? You could do a lot worse than aspire to wisdom and understanding. The Lord was pleased when Solomon asked to be blessed with “an understanding heart to judge” and to “discern between good and evil.” (1 Kings 3:9, NKJV) And the Lord said: “Because you have asked this thing, and have not asked long life for yourself, nor have asked riches for yourself, nor have asked the life of your enemies, but have asked for yourself understanding to discern justice, behold, I have done according to your words; see, I have given you a wise and understanding heart.” (1 Kings 3:11-12, NKJV) These are aspirations of the highest good. No wonder then that law, torah, which gives wisdom and understanding, is sweet to the taste, “sweeter than honey”. 

Not all studying we do in life is a delight, even if it’s necessary or useful. Sometimes we have to study subjects that aren’t all that interesting to us and that can be quite a slog. But when you’re studying something that you really find interesting, that is delightful. I really enjoy studying the sciences, which I’m fortunate enough to be able to do in my professional and academic life, as well as for pleasure. And other people have other interests. But I happen think that torah, the instruction, laws and statutes given by God in the Bible has the potential to bring universal delight to everyone, if approached receptively. It can be the kind of thing that you can’t stop thinking about, such that, like the Psalmist, you meditate on it all day. 

I believe that this delight for the torah originates in our very natures. I like the way it’s put in the Catholic Catechism: 

“Endowed with ‘a spiritual and immortal’ soul, The human person is ‘the only creature on earth that God has willed for its own sake.’ From his conception, he is destined for eternal beatitude. The human person participates in the light and power of the divine Spirit. By his reason, he is capable of understanding the order of things established by the Creator. By free will, he is capable of directing himself toward his true good. He finds his perfection ‘in seeking and loving what is true and good.’ By virtue of his soul and his spiritual powers of intellect and will, man is endowed with freedom, an ‘outstanding manifestation of the divine image.’ By his reason, man recognizes the voice of God which urges him ‘to do what is good and avoid what is evil.’ Everyone is obliged to follow this law, which makes itself heard in conscience and is fulfilled in the love of God and of neighbor. Living a moral life bears witness to the dignity of the person.” (Catechism of the Catholic Church, 1703-1706) 

I think that’s right. Our natural attraction to the good is integral to who we are. That attraction is often clouded by immoral practice but it can be purified and cultivated. As we learn and act according to the good we are developing to become the kinds of creatures that we are meant to be. The understanding and wisdom that comes from meditation on the laws and statutes given by God are the ends to which our reasoning capacities are directed. 

The Lord’s torah, instructions, statutes, and judgments include more than ethics but I will focus presently on the ethics given in scripture and tradition. The scriptural foundation for ethics is in the Ten Commandments given by God on Mount Sinai, written on tablets of stone. In what follows I’ll go through the Ten Commandments, out of order, starting with topics like murder and theft, and eventually circling in toward the core source of moral goodness in God. Some of the topics will be auxiliary to the ten commandments themselves, but are also important moral topics in Christian teaching. With many of the auxiliary topics I’ll take my lead from the 1994 Catechism of the Catholic Church, which has an excellent section on Christian moral teaching in its Part Three, “Life in Christ”. That particular text is Catholic but most of the teachings in that section agree with general Christian moral teachings. 

Thou shalt kill 

Murder is probably the most obvious moral evil. No one wants to be murdered. None of us wants the people we love to be murdered. And pragmatically we can’t have a stable society without prohibiting murder. The theological basis for condemning murder is the divine image in which human beings are created: “For in the image of God He made man.” (Genesis 9:6, NKJV) 

Human beings are made in the image of God and, because of that, are intrinsically inviolable. This is more than just a pragmatic matter. Because this inviolability is intrinsic it goes beyond just the interest of social stability. There are many instances in history where social stability was actually the justification for the murder of minority populations. But that kind of justification is absolutely impermissible. Most such justifications would probably be mistaken anyway, but even if murder had, in a perverse way, some kind social benefit it would still be inexcusable. Human beings, all human beings, are intrinsically inviolable. 

This commandment also touches on related issues like warfare, suicide, euthanasia, abortion, and bodily integrity. 

Suicide, euthanasia, and abortion are all considered forms of murder in Christian moral teaching and are all wrong. The immorality of each relates to the inviolability of human beings and the premise that the person being murdered under suicide, euthanasia, or abortion is a full human person with an inviolable right to life that no one has the right to abrogate. Absolute inviolability means that people do not even have the right to murder themselves, as with suicide. In the case of abortion, although most people agree that a human fetus in its early stages of development is a human being, not everyone agrees that the fetus is a person with an inviolable right to life. The concept “person” here being a moral category. 

Are all human beings persons? Yes. That’s what it comes down to. And there can be no other criteria for moral inviolability, i.e. the right to life. Differences in intelligence, strength, physical appearance, ability, stage of development, contribution to society, whatever, don’t make a difference to this right. Similarly people who have been injured, incapacitated, or simply aged, are no less persons with inviolability than anyone else. People are not more or less worthy of life because of their contribution to the Gross Domestic Product. There are no mere “drains on society” who are dispensable. 

It is true that there are people who are wholly dependent on others for their survival and who do not “contribute” in tangible ways. But they are no less entitled to life than anyone else. It is perhaps instructive that the first murderer defiantly challenged God with the question, “Am I my brother’s keeper?” (Genesis 4:9) Yes, absolutely. I think the Jewish philosopher Emmanuel Levinas got it right when he said that each person is infinitely responsible for everyone else. A similar idea is the line from Fyodor Dostoyevsky that, “We are all responsible for everyone else—but I am more responsible than all the others.” 

Thou shalt not steal 

Theft is another moral evil that is rather obvious. We value our possessions and we don’t want people to steal from us. We don’t want to live in conditions in which we are constantly worried that we will lose everything we own the minute we leave our homes. We also want to be able to make agreements with people with confidence that people will honor their agreements. These are basic and fairly obvious conditions for a functioning and ordered society. 

Along with stealing, the Catholic Catechism also lists the following as morally illicit: 

“Speculation in which one contrives to manipulate the price of goods artificially in order to gain an advantage to the detriment of others; corruption in which one influences the judgment of those who must make decisions according to law; appropriation and use for private purposes of the common goods of an enterprise; work poorly done; tax evasion; forgery of checks and invoices; excessive expenses and waste, willfully damaging private or public property” (Catechism of the Catholic Church, 2409). 

A related topic to the ownership of goods is the moral concern for the physical needs of the poor and vulnerable. The poor are not justified in stealing from the wealthy, but neither are the wealthy absolved of responsibility to look after the needs of the poor. This is abundantly clear in torah

“If there is among you a poor man of your brethren, within any of the gates in your land which the Lord your God is giving you, you shall not harden your heart nor shut your hand from your poor brother, but you shall open your hand wide to him and willingly lend him sufficient for his need, whatever he needs. Beware lest there be a wicked thought in your heart, saying, ‘The seventh year, the year of release, is at hand,’ and your eye be evil against your poor brother and you give him nothing, and he cry out to the Lord against you, and it become sin among you. You shall surely give to him, and your heart should not be grieved when you give to him, because for this thing the Lord your God will bless you in all your works and in all to which you put your hand. For the poor will never cease from the land; therefore I command you, saying, ‘You shall open your hand wide to your brother, to your poor and your needy, in your land.’” (Deuteronomy 15:7-11, NKJV) 

This is more than a suggestion. This is an obligation commanded in the Law. When giving these kinds of commands the Lord often reminds Israel of her former enslavement, for example: “You shall neither mistreat a stranger nor oppress him, for you were strangers in the land of Egypt.” (Exodus 22:21, NKJV) The Bible has a strong sense of what we might today call social justice. It’s not only a perversion of justice to actively steal from someone but it’s also a perversion of justice to treat someone unreasonably or with excessive harshness, even if it doesn’t technically violate a contract. For example: 

“When you lend your brother anything, you shall not go into his house to get his pledge. You shall stand outside, and the man to whom you lend shall bring the pledge out to you. And if the man is poor, you shall not keep his pledge overnight. You shall in any case return the pledge to him again when the sun goes down, that he may sleep in his own garment and bless you; and it shall be righteousness to you before the Lord your God. You shall not oppress a hired servant who is poor and needy, whether one of your brethren or one of the aliens who is in your land within your gates. Each day you shall give him his wages, and not let the sun go down on it, for he is poor and has set his heart on it; lest he cry out against you to the Lord, and it be sin to you.” (Deuteronomy 24:10-15) 

When someone is in a position of power they should still respect the person in the position of less power. A person’s home is a personal space, even if you’re lending them money, or even own the home. Even in the case of collateral, where it’s part of a contract, don’t be unreasonable. Don’t deprive a person of their means to live in comfort and dignity. Continuing: 

“You shall not pervert justice due the stranger or the fatherless, nor take a widow’s garment as a pledge. But you shall remember that you were a slave in Egypt, and the Lord your God redeemed you from there; therefore I command you to do this thing.” (Deuteronomy 24:17-18) 

Interesting that it calls this a perversion of justice. But what if everyone had agreed to the arrangement beforehand? Isn’t everyone getting exactly what was agreed to? Isn’t that just? The Lord’s notion here of justice would seem to be more than “giving everyone their due”. This kind of justice calls on the wealthier to be more generous. Continuing: 

“When you reap your harvest in your field, and forget a sheaf in the field, you shall not go back to get it; it shall be for the stranger, the fatherless, and the widow, that the Lord your God may bless you in all the work of your hands. When you beat your olive trees, you shall not go over the boughs again; it shall be for the stranger, the fatherless, and the widow. When you gather the grapes of your vineyard, you shall not glean it afterward; it shall be for the stranger, the fatherless, and the widow. And you shall remember that you were a slave in the land of Egypt; therefore I command you to do this thing.” (Deuteronomy 24:19-22, NKJV) 

This is really interesting. It’s your field. Don’t all the sheaves, olives, and grapes rightfully belong to you? Actually, no. It’s a fascinating concept of justice at work here. 

Thou shalt not bear false witness against thy neighbor 

Lying takes many forms. Bearing false witness against a person has to be one of the worst forms. Slander, libel, defamation – these are ugly and inexcusable actions. We ought not underestimate how important our reputations are to us. Unfortunately we cannot expect that we will always have the reputations we deserve. In fact we’ve been warned about the opposite, that disciples of Christ will have all manner of evil spoken against them falsely (Matthew 5:11). That will happen. But wo to the person who perpetrates these kinds of falsehoods. Bearing false witness can cause financial damage but I think the social damage is even worse. 

To love God is to love the truth. Jesus said, “I am the way, the truth, and the life” (John 14:6) and Psalmist said, “Your law is truth” (Psalm 119:142). The Catechism says: “Man tends by nature toward the truth. He is obliged to honor and bear witness to it: ‘It is in accordance with their dignity that all men, because they are persons . . . are both impelled by their nature and bound by a moral obligation to seek the truth, especially religious truth. They are also bound to adhere to the truth once they come to know it and direct their whole lives in accordance with the demands of truth.” (Catechism of the Catholic Church, 2467) Why again, when studying torah, this delight, “O how love I thy law! it is my meditation all the day”? Because it’s in our nature. We are impelled toward truth, we are bound, morally, to seek and adhere to truth. 

Truth isn’t merely propositional but also morally inflected. Aristotle said, “To say that that which is, is not, and that which is not, is, is a falsehood; therefore, to say that which is, is, and that which is not, is not, is true” (Aristotle, Metaphysics, 1011b26). Yes, for sure. But it’s also a moral principle. To say that that which is, is not, and that which is not, is, is wrong. It’s an offense against reality and against justice. 

Thou shalt not commit adultery 

Sex is either something we think too much about or not enough about. I’m reminded of Alain de Botton’s playful book title How to Think More About Sex. The title is playful because by “think” he doesn’t mean mere sexual fantasy but rather critical thinking. What part does sexuality play in the overall scheme of things? 

The Catechism states: “Chastity means the successful integration of sexuality within the person and thus the inner unity of man in his bodily and spiritual being. Sexuality, in which man’s belonging to the bodily and biological world is expressed, becomes personal and truly human when it is integrated into the relationship of one person to another, in the complete and lifelong mutual gift of a man and a woman. The virtue of chastity therefore involves the integrity of the person and the integrality of the gift.” (Catechism of the Catholic Church, 2337) 

Something interesting to observe in this statement is that chastity and sexuality are not opposites. Rather chastity is sexuality directed toward its proper ends. What kind of beings are we? We are certainly members of the bodily and biological world. We are mortal. And we only persist as a species through sexual reproduction. Sexuality is the way in which belonging to the bodily and biological world is expressed. In a certain sense all of ethics concerns the successful integration of the multiple aspects of our being toward those ends for which we are created. And that’s what chastity is for sexuality. 

An important concept pertaining to chastity is “integrity”. The primary definition of “integrity” is general moral uprightness. But another definition of particular relevance here is of a state of being whole and undivided, having all parts integrated into a coherent unity. The Catechism states: “The chaste person maintains the integrity of the powers of life and love placed in him. This integrity ensures the unity of the person; it is opposed to any behavior that would impair it. It tolerates neither a double life nor duplicity in speech.” (Catechism of the Catholic Church, 2338) This is an interesting concept that can certainly apply to other aspects of personhood in addition to sexuality. Continuing on: “Chastity includes an apprenticeship in self-mastery which is a training in human freedom. The alternative is clear: either man governs his passions and finds peace, or he lets himself be dominated by them and becomes unhappy.” (Catechism of the Catholic Church, 2339) 

Underlying all of this is the sanctity of marriage. Jesus said: “Have you not read that He who made them at the beginning ‘made them male and female,’ and said, ‘For this reason a man shall leave his father and mother and be joined to his wife, and the two shall become one flesh’? So then, they are no longer two but one flesh. Therefore what God has joined together, let not man separate.” (Matthew 19:4-6) This union is a very serious matter. And hence the gravity of adultery. The union is designed by God for the unitive and procreative purpose. 

Marriage of male and female persons is what sexuality is for and is normative for it. Violations of chastity include adultery, rape, fornication, prostitution, lust, pornography, masturbation, and homosexuality. 

Rape especially is an extremely serious offense. It is not only a perversion of the divinely ordained purposes of sexuality but is also violent. It is also a uniquely horrific act of violence because it is sexual, and thus much more horrific even than a regular assault. Sexual assault is a more accutely personal and existential attack. And our appropriately intense and visceral response to it indicates how deeply sexuality is situated at the core of our being and identity. 

Thou shalt not covet 

The forbidding of covetousness is interesting because it pertains to thoughts rather than physical actions. Our moral character and virtue is defined by our mental actions. A succinct expression of this outlook is the proverb: “For as he thinks in his heart, so is he.” (Proverbs 23:7, NKJV) 

For example, the commandment says, “thou shalt not covet thy neighbor’s wife” (Exodus 20:17, KJV). This goes beyond but also extends from the commandment against adultery. To be sure, it is wrong to commit adultery. But it is also wrong to desire another man’s wife. Chastity is not only physical but is also mental. A clear example of this is Jesus’s teaching: 

“You have heard that it was said to those of old, ‘You shall not commit adultery.’ But I say to you that whoever looks at a woman to lust for her has already committed adultery with her in his heart. If your right eye causes you to sin, pluck it out and cast it from you; for it is more profitable for you that one of your members perish, than for your whole body to be cast into hell. And if your right hand causes you to sin, cut it off and cast it from you; for it is more profitable for you that one of your members perish, than for your whole body to be cast into hell.” (Matthew 5:27-30, NKJV) 

The most extreme example of an offense of this kind is pornography where a person is actively seeking and leering at people lustfully. This is extremely destructive to a person’s soul. Modern communications enables us to access an unlimited number of images on a scale previously unimaginable. The commandment and teaching of Jesus condemns leering and lusting after even just one person as a very serious sin.

This kind of statute relating to mental actions is in tension with more modern moral ideas like the “harm principle” as promoted by the philosopher John Stuart Mill, where actions are only immoral if they cause harm to others. We find anything beyond this invasive. What goes on inside my head is no one else’s business. But the Lord’s torah is much more extensive than this and goes deeper into the state of one’s soul. 

Beyond sexuality we are also commanded to cultivate our thoughts in all our relations to others. “You shall not covet your neighbor’s house… nor his ox, nor his donkey, nor anything that is your neighbor’s.” (Exodus 20:17, NKJV) Today we might say that we must not covet our neighbor’s job, our neighbor’s car, our neighbor’s investment portfolio, our neighbor’s social prestige, etc. Thinking like that is not a proper way to live. And if you think about it, it’s certainly a way to be miserable. There’s wisdom in the idea that comparison is the thief of joy. It’s no way to live with yourself or with others in fellowship. 

Honour thy father and thy mother 

The family plays a central part in God’s creation, starting with husband and wife, father and mother. God has joined husband and wife together (Matthew 19:4-6) and commanded them to “Be fruitful and multiply” (Genesis 1:28, NKJV). Father and mother are the divinely appointed leaders and teachers of their children. 

The Catechism states: “In creating man and woman, God instituted the human family and endowed it with its fundamental constitution. Its members are persons equal in dignity. For the common good of its members and of society, the family necessarily has manifold responsibilities, rights, and duties.” (Catechism of the Catholic Church, 2203) 

The philosopher Roger Scruton distinguished between the kinds of rights and responsibilities created by agreement, as with a contract, and the kinds of rights and responsibilities that we have for reasons beyond anything we chose; what he calls “sacred obligations” (Scruton, On Human Nature, 113-117). Family responsibilities, rights, and duties are of this second type. Children do not choose to be born, nor to be born to the parents they’re born to. Nevertheless they have responsibilities of filial piety. And parents do not choose the character and personality of their children. We take then as they come. Another philosopher, Michael Sandel, has called this “openness to the unbidden” (Sandel, The Case Against Perfection). Parents are obligated to care for them and teach them, regardless of the unique and unforeseen challenges that come with each individual child. As Scruton puts it: “The field of obligation is wider than the field of choice. We are bound by ties that we never chose, and our world contains values and challenges that intrude from beyond the comfortable arena of our agreements.” (Scruton, 116) Nowhere is this more relevant than in family responsibilities. 

What do parents owe to their children? The Catechism states that parents must respect their children as human persons, educate their children, create a home “where tenderness, forgiveness, respect, fidelity, and disinterested service are the rule”, teach them “self-denial, sound judgment, and self-mastery”, initiate them into “solidarity and communal responsibilities”, teach them to “avoid the compromising and degrading influences which threaten human societies”, and teach them the gospel of Jesus Christ (Catechism of the Catholic Church, 2221-2226). 

What do we owe to our parents? When we are children we owe them obedience and respect. The Catechism states, “Obedience toward parents ceases with the emancipation of the children; not so respect, which is always owed to them.” As adults we must, as much as we are able, “give them material and moral support in old age and in times of illness, loneliness, or distress.” 

Remember the sabbath day, to keep it holy 

Labor is part of the human condition, something illustrated in Genesis with God’s words to Adam: 

“Cursed is the ground for your sake;
In toil you shall eat of it
All the days of your life.
Both thorns and thistles it shall bring forth for you,
And you shall eat the herb of the field.
In the sweat of your face you shall eat bread
Till you return to the ground,
For out of it you were taken;
For dust you are,
And to dust you shall return.”
(Genesis 3:17-19, NKJV)

Nevertheless, we are ordained to more than endless toil. God has ordained that we should have periodic and regular rest. Rest is not just for a privileged elite. Everyone must have rest from labor on the Sabbath: 

“In it thou shalt not do any work, thou, nor thy son, nor thy daughter, thy manservant, nor thy maidservant, nor thy cattle, nor thy stranger that is within thy gates.” (Exodus 20:10) 

This includes laborers, service workers, migrants; everyone. This reprieve even extends to the animals that labor for us. As important as it is to rest from our own labors on the Sabbath it is just as important, maybe even more important to enable others to rest. As stated in the Catechism: 

“Those Christians who have leisure should be mindful of their brethren who have the same needs and the same rights, yet cannot rest from work because of poverty and misery… Sanctifying Sundays and holy days requires a common effort. Every Christian should avoid making unnecessary demands on others that would hinder them from observing the Lord’s Day.” 

This is a Sabbath perspective that ought to affect the way we view ourselves and others generally. Who am I beyond my labor and career? Who are other people to me beyond the benefit that I can get from them in the goods and services they provide me? 

Thou shalt not take the name of the Lord thy God in vain 

One of the important concepts in the Law given by God through Moses is that of holiness. Certain things are marked out as qadosh, radically separate and other from the ordinary. God is loving but his holiness also requires singular reverence. But his holiness doesn’t diminish his love and goodness. These attributes all cohere together as one in a way unique to God. An apt illustration of this is C.S Lewis’s description of Aslan, a type for Christ, in The Lion, the Witch and the Wardrobe

“‘Aslan is a lion- the Lion, the great Lion.’ ‘Ooh’ said Susan. ‘I’d thought he was a man. Is he-quite safe? I shall feel rather nervous about meeting a lion’…’Safe?’ said Mr Beaver …’Who said anything about safe? ‘Course he isn’t safe. But he’s good.’” 

I think the most powerful example of this principle in scripture comes in the episode after the people of Israel had fallen into idolatry and worshiped before the golden calf, an unimaginably grave offense before God. The Lord told Moses that he could not stay with them but would instead send an angel, a messenger, in his place. 

“Then the Lord said to Moses, ‘Depart and go up from here, you and the people whom you have brought out of the land of Egypt, to the land of which I swore to Abraham, Isaac, and Jacob, saying, ‘To your descendants I will give it.’ And I will send My Angel before you… for I will not go up in your midst, lest I consume you on the way, for you are a stiff-necked people.’” (Exodus 33:1-3) 

The Lord is good but he is not safe. That’s why he was hesitant to journey with the people. He knew that his holiness was hazardous to the people in their wickedness. Still he did go up with them. And he did not desire that they be distant from him. Rather he instituted laws and statutes for them to be holy like him. 

“Now therefore, if you will indeed obey My voice and keep My covenant, then you shall be a special treasure to Me above all people; for all the earth is Mine. And you shall be to Me a kingdom of priests and a holy nation.” (Exodus 19:6) 

We should keep these things in mind when we speak of God and approach God with the proper reverence. 

The Catechism states: “Respect for his name is an expression of the respect owed to the mystery of God himself and to the whole sacred reality it evokes. the sense of the sacred is part of the virtue of religion” (Catechism of the Catholic Church, 2144). 

I am the LORD thy God 

We end now with the first commandment. I wanted to save this one for last because I think of this as the foundation for all of ethics. What is it that gives the laws and statutes their authority? “I am the LORD thy God” (Exodus 20:2). What follows that statement is absolutely authoritative, coming directly from the source of truth, goodness, beauty, and all that is. Nachmanides (1194 – 1270), also known as Ramban, said in his commentary on this verse: 

“He said, I am the Eternal, thus teaching and commanding them that they should know and believe that the Eternal exists and that He is G-d to them. That is to say, there exists an Eternal Being through Whom everything has come into existence by His will and power, and He is G-d to them, who are obligated to worship Him.” (Ramban on Exodus 20:2) 

The Lord also says, “Thou shalt have no other gods before me.” (Exodus 20:3) Which we can interpret either as having other gods in priority over the Lord or even simply in the presence of the Lord, even if in equal position. I think one possible way to summarize the whole of the Hebrew Scripture would be as Israel’s continual temptation with idolatry. 

The Catechism states: “Idolatry consists in divinizing what is not God. Man commits idolatry whenever he honors and reveres a creature in place of God, whether this be gods or demons (for example, satanism), power, pleasure, race, ancestors, the state, money, etc.” (Catechism of the Catholic Church, 2113). 

This first commandment is foundational. It addresses the matter of where goodness itself comes from in the first place and it also precludes the possibility that there could be any other source. What else could be the source for goodness and ethical principles? Power? Pleasure? The state? Economic output? There are ethical systems with each of these as a philosophical or ideological foundation. And each has a compelling case that is, to a limited extent, intellectually satisfying. But I don’t think that any of them is ultimately intellectually satisfying, nor ultimately emotionally or spiritually satisfying. 

What should we expect and hope to receive from the law? In the end we want answers to the question, “how should I live?” Does it ultimately matter how I live? If it does matter how I live, why does it matter? On what basis? I think these questions are naturally related to the question of what kind of beings we are. What are we and why do we exist? What do we exist for? It all goes back to this first commandment: I am the LORD thy God. How we should act and what we should do ties back to our origin in God. 

Human beings are the tzelem elohim, the image of God. So to understand what kind of beings we are and how we can fulfill our nature we should look to God. What attributes are constitutive of our divine nature? Holiness, justice, loving-kindness, mercy, faithfulness, honor. We are also embodied, spiritual, mental, mortal, dependent, sexual, emotional, social, familial, and rational. All of these attributes have moral implications that are addressed in God’s laws and statutes. Our fulfillment requires spiritual practice, reverence for God, filial piety, responsibilities to family members, sexual discipline, concern for the physical needs of others, respect for the physical body and for life, and discipline of the mind. God’s laws and statutes set forth the foundational ethical principles for how to fulfill our nature as human beings and as image bearers of God’s nature.

The Trinity

The doctrine of the Trinity is very important in Christianity. But people who are not Trinitarians, even non-Trinitarians who believe in the Bible and in Jesus, might wonder, what’s the reason for believing in the Trinity? Is the idea of the Trinity motivated from Biblical texts or was it something that came out of Greek philosophy or Greek culture in early Christianity? How did Christians come to understand things in this way? And why has this understanding persisted in Christian history?

With this episode I’d like to get into some more systematic theology. In a previous episode I went over the nature of God as it has been formulated in the theological and philosophical tradition of classical theism. The topic of this episode, the Trinity, is also about the nature of God but more especially about the uniquely Christian understanding of the nature of God as the triune God, God as Trinity: Father, Son, and Holy Spirit.

The doctrine of the Trinity is very important in Christianity. But people who are not Trinitarians, even non-Trinitarians who believe in the Bible and in Jesus, might wonder, what’s the reason for believing in the Trinity? How did Christians come to understand things in this way? And why has this understanding persisted in Christian history? Is the idea of the Trinity motivated from Biblical texts or was it something that came out of Greek philosophy or Greek culture in early Christianity? Or even more basic, what is the doctrine of the Trinity, really? I think these are good questions and quite common questions. So it’s a topic worth looking at.

I’ll go through this topic in seven sections: (1) a definition of the Trinity, (2) some misinterpretations of the Trinity, (3) the scriptural motivation for the doctrine of the Trinity, (4) some of the cultural and philosophical background, (5) some useful theological terms, (6) some history of the development of the doctrine, and (7) the significance of the doctrine of the Trinity to the whole Christian faith.


One definition of the Trinity I think is quite good is one with the following seven parts.

The Father is God.
The Son is God.
The Holy Spirit is God.
The Father is not the Son.
The Son is not the Holy Spirit.
The Holy Spirit is not the Father.
There is only one God.

I picked up this definition from Phillip Cary in his Teaching Company course The History of Christian Theology. And he adapted this from Augustine of Hippo (354 – 430). This definition is quite straightforward, I think. And we’ll see later how there are scriptural motivations for each of these statements. Each of the statements, taken individually, isn’t hard to understand. It’s trying to understand how they can all fit together that gets challenging. And that’s where a lot of the additional terms and concepts come in; like substance, persons, generation, and procession. But the most basic content of the definition, which all these other concepts are based on, consists of these very basic ideas. God is Father, Son, and Holy Spirit. Each of them is God. They are not the same person. And there is only one God.


That’s what the Trinity is. It’s also good to understand what the Trinity is not. There are two major misunderstandings of the Trinity, that make the mistake of either confounding the persons or dividing the essence. These two misinterpretations are modalism and tritheism.

Modalism is the view that the Father, Son, and Holy Spirit are all the same person. That each is merely a mode that God can take on. One proponent of this view in history was a man named Sabellius in the third century A.D. So this idea is also sometimes called Sabellianism. I think this is a pretty common misunderstanding of the Trinity, for both non-Trinitarians and even many Trinitarians. It’s easy to see where this comes from. If there’s only one God and the Father, Son, and Holy Spirit are God, then just say they’re all the same person. But this is quite clearly scripturally untenable, as we’ll see in the next section. We shouldn’t try to imagine that Jesus prayed to himself or spoke of himself in the third-person as if he were his own Father.

Tritheism is the view that there are three Gods: the Father, Son, and Holy Spirit. It’s also easy enough to see where this comes from. If the Father, Son, and Holy Spirit are God, then just say there are three Gods. But this is also quite clearly scripturally untenable. Monotheism is one of the most emphatic teachings of both the Old and New Testaments. Granted, the Ancient Israelites were not very good at following this and were almost irrepressible relapsing polytheists. But the prophets of the Lord were uncompromising and zealous monotheists, continually reproving the people and calling them to repent and to forsake polytheism. While there are other divine beings like angels in the Bible, they are subordinate to the one creator God. There’s no room for three such capital G Gods in the scriptures.

Scriptural Motivation

More than any other source, more than tradition, reason, or culture, the most important and authoritative source of doctrine in Christianity is in scripture. The doctrine of the Trinity is not explicitly taught in the Bible. But the doctrine is scripturally motivated. If we ask, “what is it that motivates Christians to formulate the doctrine of the Trinity?” we can find those motivations in scripture. It doesn’t come from nowhere.

There are two main groups of scriptures that motivate the doctrine of the Trinity. First, scriptures that affirm that there is only one God. And second, scriptures that affirm that Jesus is God. Other kinds of scriptures include those that affirm that the Father is God, that the Holy Spirit of God, and that they are not all the same person.

The most significant of the monotheistic passages is the Shema in Deuteronomy 6:4.

“Hear, O Israel: The Lord our God, the Lord is one!”

This is a kind of first article of faith for the religion of Israel. It’s the one Jesus called the first and greatest commandment (Matthew 22:38). The first of the Ten Commandments are similar.

“I am the Lord your God, who brought you out of the land of Egypt, out of the house of bondage. You shall have no other gods before Me.” (Exodus 20:2-3)

Among the Old Testament prophets Second Isaiah is especially emphatic in his monotheism:

Isaiah 43:12
“You are My witnesses,” says the Lord,
“And My servant whom I have chosen,
That you may know and believe Me,
And understand that I am He.
Before Me there was no God formed,
Nor shall there be after Me.”

Isaiah 44:6
“Thus says the Lord, the King of Israel,
And his Redeemer, the Lord of hosts:
‘I am the First and I am the Last;
Besides Me there is no God.’”

That’s the monotheistic foundation. One God, the Lord God of Israel. As we come to the New Testament we find passages of scriptures that indicate that this same God is actually three persons. After his Resurrection, at the moment of his Ascension, Jesus commissioned his apostles in Matthew 28:19.

“Go therefore and make disciples of all the nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit”

Interesting that it’s the name, singular, ὄνομα (onoma), of the Father, Son, and Holy Spirit, rather than the names. This baptismal formula calls for baptism in the name of the three persons of the Trinity. We see elsewhere that the three persons are invoked in blessing, as with Paul in 2 Corinthians 13:14.

The grace of the Lord Jesus Christ, and the love of God, and the communion of the Holy Spirit be with you all. Amen.

In the scriptures Jesus doesn’t ever say explicitly, “I am God”. Some conclude from this is that the early Christians actually didn’t believe that he was God and that this idea developed later. I don’t think that theory works, but that’s another topic. Even without that kind of direct statement there are many reasons to conclude from the scriptures that Jesus is God.

The Gospel of John opens placing Christ at the Creation of all things in the prologue of John 1:1-5.

In the beginning was the Word, and the Word was with God, and the Word was God. He was in the beginning with God. All things were made through Him, and without Him nothing was made that was made. In Him was life, and the life was the light of men. And the light shines in the darkness, and the darkness did not comprehend it.

Paul also taught of an exalted origin when he quoted what appears to have been a very, very early Christian hymn about Jesus, in Philippians 2:5-11.

Let this mind be in you which was also in Christ Jesus, who, being in the form of God, did not consider it robbery to be equal with God, but made Himself of no reputation, taking the form of a bondservant, and coming in the likeness of men. And being found in appearance as a man, He humbled Himself and became obedient to the point of death, even the death of the cross. Therefore God also has highly exalted Him and given Him the name which is above every name, that at the name of Jesus every knee should bow, of those in heaven, and of those on earth, and of those under the earth, and that every tongue should confess that Jesus Christ is Lord, to the glory of God the Father.

That’s quite exalted language. The name which is abovery name. Jesus Christ is Lord. Lord is the word traditionally substituted for the name of God, YHWH. “Jesus is Lord” is probably the earliest Christian confession. Essentially another version of “YHWH is Lord”.

Paul has similarly exalted language for Jesus when he says in Colossians 2:9.

For in Him dwells all the fullness of the Godhead bodily.

In the Gospel of John Jesus makes a number of conspicuous “I am” statements, basically invoking the name of God as revealed to Moses in Exodus 3:14, “I AM THAT I AM”. For example in John 8:58.

Jesus said to them, “Most assuredly, I say to you, before Abraham was, I AM.”

And Jesus’ disciple Thomas actually calls him God in John 20:27-28.

Then He said to Thomas, “Reach your finger here, and look at My hands; and reach your hand here, and put it into My side. Do not be unbelieving, but believing.” And Thomas answered and said to Him, “My Lord and my God!”

In John Jesus also teaches about his oneness with the Father. In John 10:30.

“I and My Father are one.”

And in John John 14:9-11.

He who has seen Me has seen the Father; so how can you say, ‘Show us the Father’? Do you not believe that I am in the Father, and the Father in Me? The words that I speak to you I do not speak on My own authority; but the Father who dwells in Me does the works. Believe Me that I am in the Father and the Father in Me, or else believe Me for the sake of the works themselves.

This unity notwithstanding, it is clear from multiple instances in the scriptures that the Father and the Son are not the same person. For example at Jesus’ baptism in Matthew 3:16-17.

When He had been baptized, Jesus came up immediately from the water; and behold, the heavens were opened to Him, and He saw the Spirit of God descending like a dove and alighting upon Him. And suddenly a voice came from heaven, saying, “This is My beloved Son, in whom I am well pleased.”

The Father, Son, and Holy Spirit are all spoken of distinctly here. Jesus is also always praying to the Father, with no indication that he is in any way praying to himself. Even in their intimate unity there is distinction, as shown wonderfully in John 17:20-23.

“I do not pray for these alone, but also for those who will believe in Me through their word; that they all may be one, as You, Father, are in Me, and I in You; that they also may be one in Us, that the world may believe that You sent Me. And the glory which You gave Me I have given them, that they may be one just as We are one: I in them, and You in Me; that they may be made perfect in one, and that the world may know that You have sent Me, and have loved them as You have loved Me.”

These and other scriptures indicate that: there is only one God, that the Father, Son, and Holy Spirit are God, and that they are not all the same person.

Cultural and Philosophical Background

Christianity developed in a highly Hellenized, Greek-speaking environment. Even important Jewish leaders of early Christianity, like Paul of Tarsus, spoke and wrote in Greek and were immersed in Greek culture. The Jewish scripture for many outside of Judea was the Septuagint, a Greek translation of the Hebrew scriptures. An important Jewish theologian and philosopher of the time period, Philo of Alexandria (20 B.C. – 50 A.D.) wrote all his works in Greek and he was well-versed in Platonic philosophy.

There is a line of thought that Greek culture and philosophy was the real source of many Christian theological developments, rather than scripture. One prominent proponent of this view was Adolf Von Harnack (1851 – 1930). I happen to think this position is overstated and agree with Robert Louis Wilken that “the time has come to bid a fond farewell to the ideas of Adolf von Harnack” and that rather than positing the Hellenization of Christianity “a more apt expression would be the Christianization of Hellenism” (The Spirit of Early Christian Thought, xvi). Greek culture and philosophy are sometimes thought to have invaded and supplanted the original Hebrew foundation. But this world was already immersed in Greek influence, even the Jewish part of it. Certainly Jews and Christians drew from the ideas available to them in the surrounding culture, but in a way that was subordinate to and in the service of scripture. Robert Louis Wilkin made this observation of the writings of the Early Church Fathers:

“To be sure, many of the best minds in the early church were philosophically astute and moved comfortably within the intellectual tradition of the ancient world… But if one picks up a treatise of Origen or Basil of Caesarea and compares it with the writings of the philosopher Alcinous or the neo-Platonist Plotinus, it is apparent at once that something else is at work. For one thing… they turn always to the Bible as the source of their ideas. No matter how rigorous or abstruse their thinking–for example, in dealing with a complex and subtle topic like the distinctive identity of each person of the Trinity–Christian thinkers always began with specific Biblical texts. I have found that it is not possible to read the church fathers without the Bible open before me. The words of the Scriptures crowd the pages of their books and essays, and their arguments often turn on specific terms or phrases from the Bible. But one can detect something else in their writings, at once closer to experience yet more elusive. On page after page the reader senses that what they believe is anchored in regular, indeed habitual, participation in the church’s worship, and what they teach is confirmed by how they pray.”

This has also been my experience in reading the Early Church Fathers.

Something interesting that we get from Greeks are philosophical ideas that are quite amenable to monotheism, converging on a similar idea that we get through revelation in the Old Testament. Greek pagans, among the regular folk, were polytheists. But the more educated, intellectual, and philosophical Greek pagans tended to trace everything back to some single ultimate source. For Plato (c. 428 – c. 348 BC) this was The Good, for Aristotle (384 – 322 BC) this was the Unmoved Mover, for Plotinus (c. 204 – 270 AD) this was The One. Both reason and revelation pointed to the reality of a single first principle or God over all things. Early Church Fathers well-versed in both scripture and philosophy, like Justin Martyr (100 – 165), Origen of Alexandria (185 – 253), and Clement of Alexandria (150 – 215), could find both sources quite harmonious. Both reason and revelation were important sources in support of the foundational idea of the doctrine of the Trinity: that there is only one God.


It’s possible to define the Trinity in very simple terms, like the seven listed earlier. Those simple terms are sufficient for many purposes. They certainly were for the earliest Christians. Still, as Christians have thought more deeply about the Trinity they have found it helpful to expand their vocabulary to cover more sophisticated concepts and to distinguish them from heretical views. Before people had these terms available to them they might ask questions about the Trinity like “one what?” and “three whos?” What kinds of things are we talking about here? There weren’t terms available to tag these sorts of concepts to get a hold of them. There aren’t terms in scripture to use for these sorts of philosophical questions. But they are interesting questions. They’re terms that we can use if we want to take things to the “next level”. Let’s look at five such terms.

Substance, Homoousion, Essence

This is a term for the “one what?” question. The Greek term οὐσία (ousia) is essence or substance. The Council of Nicea used this term to describe what it is in their essence as God, that the Father, Son, and Holy Spirit share. They are the same in essence, ὁμοούσιον (homoousion), one ousia.

Persons, Hypostases

Hypostasis (ὑπόστασις) is a term for the “three whos?” question. This is an especially good example of a term that was appropriated and repurposed to make a fine distinction that wasn’t conceptualized previously. (It’s quite interesting how language can extend our thinking in this way). Hypostasis had meant something very similar to ousia. But it was later made distinct to refer to that in the Trinity which should not be confounded, the persons of the Father, Son, and Holy Spirit. Using the terms ousia and hypostasis the Trinity can be described as three hypostases, one ousia; three persons, one essence.


Perichoresis (περιχώρησις) is a term to used to refer to the relations between the three persons of the Trinity. It means “going around” and when used to describe the Trinity it refers to their particular interrelation or interpenetration. As used historically in the writings of theologians like Maximus Confessor (c. 580 – 662), Gregory of Nazianzus (329–389), and John of Damascus (c. 675 – 749) it conveys a sense of motion, dynamism, even a kind of eternal dance between the Father, Son, and Holy Spirit. This idea has special currency for the mystical side of Christianity, in pursuit of direct, experiential, and personal relationship with the Triune God.

Eternal Generation, Eternal Begetting

The Nicene Creed states that Christ is “begotten, not made”, γεννηθέντα, οὐ ποιηθέντα (gennethenta, ou poiethenta). The point being that the Son is not a creature, not created by the Father. But he is begotten, or put another way, generated by the Father. Is this a distinction without a difference? No. Unlike any created being, the Son exists necessarily and eternally, just like the Father. Each has life in himself. “For as the Father has life in Himself, so He has granted the Son to have life in Himself”. (John 5:26) There’s a relation of begetter and begotten. But this is something more akin to a logical process than a process in time.

A geometrical analogy of generation that comes to mind is the relation of the center point of a circle to all the points on its circumference. By definition all points on a circle are equidistant from the center of the circle. In a sense the center point generates all the points on the circle. But which part comes first? Well neither really comes first. The relation doesn’t even come to be in any kind of temporal process. There’s a relation there but it’s just there, without needing to have ever started, much less one part before another.

One philosophy contemporary with the Council of Nicea, Neoplatonism, certainly provided intellectual tools to come up with this kind of idea. In the metaphysics of Plotinus (204 – 270) all things are understood to derive from a single great source, an absolute One. The first level of emanation from this One is the Divine Mind. The One eternally generates the Divine Mind in a way very similar to the way Christian theologians understood the Father to generate the Son.


In the Nicene Creed it is said that the Holy Spirit “proceeds from the Father”, τὸ ἐκ τοῦ Πατρὸς ἐκπορευόμενον (to ek tou Patros ekporeuomenon). Catholics and Protestants also say that the Holy Spirit proceeds from the Father and from the Son. Filioque in Latin. One example from scripture for this idea is John 14:23,

But the Helper, the Holy Spirit, whom the Father will send in My name, He will teach you all things, and bring to your remembrance all things that I said to you.


A key historical moment for the development of the doctrine of the Trinity was the Council of Nicea in 325. The Council was a response to the teachings of Arius (265 – 336). Arius taught that the Son, Jesus Christ, was a creature, a creation of the Father, the first and greatest of God’s created beings, but still a created being. The key idea of this doctrine was that “there was a time when he was not”.

Arius’ teachings were very influential, not just among clergy and theologians but even among regular folks. Gregory of Nyssa (335 – 395) described the controversy in this way:

“The whole city is full of it, the squares, the marketplaces, the crossroads, the alleyways; rag dealers, money-changers, food-sellers, they are all busy arguing. If you ask someone to give you change, he philosophizes about the Begotten and the Unbegotten; if you inquire about the price of a loaf, you are told by way of reply that the Father is greater and the Son inferior; if you ask, “Is my bath ready?” the attendant answers that the Son was made out of nothing.” (“On the Deity of the Son” PG xlvi, 557b)

Πάντα γὰρ τὰ κατὰ τὴν πόλιν τῶν τοιούτων πεπλήρωται͵ οἱ στενωποὶ͵ αἱ ἀγοραὶ͵ αἱ πλατεῖαι͵ τὰ ἄμφοδα· οἱ τῶν ἱματίων κάπηλοι͵ οἱ ταῖς τραπέζαις ἐφεστη κότες͵ οἱ τὰ ἐδώδιμα ἡμῖν ἀπεμπολοῦντες. Ἐὰν περὶ τῶν ὀβολῶν ἐρωτήσῃς͵ ὁ δέ σοι περὶ γεννητοῦ καὶ ἀγεννήτου ἐφιλοσόφησε· κἂν περὶ τιμήματος ἄρτου πύθοιο͵ Μείζων ὁ Πατὴρ͵ ἀποκρίνεται͵ καὶ ὁ Υἱὸς ὑποχείριος. Εἰ δὲ͵ Τὸ λουτρὸν ἐπιτήδειόν ἐστιν͵ εἴποις͵ ὁ δὲ ἐξ οὐκ ὄντων τὸν Υἱὸν εἶναι διωρίσατο. Οὐκ οἶδα τί χρὴ τὸ κακὸν τοῦτο ὀνομάσαι͵ φρενῖτιν ἢ μανίαν͵ ἤ τι τοιοῦτον κακὸν ἐπιδήμιον͵ ὃ τῶν λογι σμῶν τὴν παραφορὰν ἐξεργάζεται.

So the Church had to ask, what do we say about this? Is this right? The First Council of Nicea (325) and the Nicene Creed were the result. The Nicene Creed was later adjusted further in the First Council of Constantinople (381) to the version in use today. In response to Arius the Nicene Creed affirmed that Jesus Christ is:

“Begotten of the Father; Light of Light, very God of very God, begotten, not made, consubstantial with the Father”

The key being that Jesus is God. That was the line drawn.

There were also some very significant theologians and texts written following the council that have been important in the history of Christian theology, especially theology of the Trinity. Some theologians of special note are

Athanasius of Alexandria (296 – 373)
Basil the Great (330 – 379)
Gregory of Nyssa (c. 335 – c. 395)
Gregory of Nazianzus (329–389)
Augustine of Hippo (354 – 430)
Hilary of Poitiers (310 – 367)

Arianism continued to be a prominent view, sometimes supported by the Roman Empire. And many of the Barbarian kingdoms in the West were Arians. These theologians worked diligently to teach the orthodox view against Arianism.

One of the most significant texts of this period was Augustine of Hippo’s On the Trinity (De Trinitate). It’s not only an impressive theological defense and explanation of the Trinity but it also ends up being a fascinating work on the philosophy of the mind and personal identity. This was because Augustine pursued the idea that human beings, being created in the image of God, must be created in the image of the Trinity and therefore bear features of the Trinity in themselves and in their minds.


In his Intercessory Prayer in John 17:3 Jesus said to the Father:

And this is eternal life, that they may know You, the only true God, and Jesus Christ whom You have sent.

Knowing God is foundational to Christian life. This means knowing both the Father and his son Jesus Christ. And also the Holy Spirit, who testifies of both. This brings home the importance of Jesus Christ to Christian faith.

This is what makes Christianity unique. There are other monotheistic religions and even monotheistic philosophies. But the unique and special revelation of Christianity is the one we find in Jesus Christ.