The hocus-pocus phantasm of a god like another Cerberus with one body and three heads had it's birth and growth in the blood of thousands and thousands of martyrs.... In fact the Athanasian paradox that one is three, and three but one is so incomprehensible to the human mind that no candid man can say he has any idea of it, and how can he believe what presents no idea. He who thinks he does only decieves himself.1
Which shows that Jefferson, brilliant in so many ways, was a horrible theologian.2 However, his question remains a good one. How can anyone be so insipid to believe 3 = 1? This used to be one of the major objections I myself hurled at Christianity. In fact, being a lover of American history that I am, I used to use this passage from Jefferson to show the ludicrousness of it all. It seemed obvious enough, indeed (to use another set of Jeffersonian words) it seemed like a truth to be held as self-evident that three is in no way one nor is one, three. And that should be that for the Christian God.
But thinking on the matter a bit longer makes one realize that the Christian doctrine of the Trinity is neither so simple nor so easily refuted as Jefferson (and my younger self) so confidently thought it was. Christians, I later learned, do not believe in one God who is three Gods. They believe in one God who is three persons. Of course, something can be one in one way and three in another way, that's no contradiction. I can be one person, yet hold three jobs, for example. It turned out, Christians could do basic math after all.
But what would this God be like? Was Jefferson still right when he said no human mind could comprehend the Trinity? Not exactly. First, Jefferson has confused being able to "comprehend" something with being able to imagine it. We can't quite imagine a three personal God, but we can, at least begin, to comprehend Him.
Frank Sheed, in his classic, Theology and Sanity, gives a great summary of the problem of confusing imagination with comprehension,
The first difficulty in the way of the intellect's functioning well is that it hates to function at all, at any rate beyond the point where functioning begins to require effort. The result is that when any matter arises which is properly the job of the intellect, then either nothing gets done at all, or else the imagination leaps in and does it instead.... Consider what imagination is. It is the power we have of making mental pictures of the material universe. What our senses have experienced... can be reproduced by the imagination.... What the senses cannot experience, the imagination cannot make pictures of.... To say that something is unimaginable is merely to say that the imagination cannot make a picture of it. But pictures are only of the material world; and to that imagination is limited. Naturally it cannot form pictures of spiritual realities, angels, or human souls, or love or justice.... To complain that a spiritual thing is unimaginable would be like complaining that the air is invisible....Thus the reality of any spiritual statement must be tested by the intellect, not by the imagination. The intellect's word of rejection is "inconceivable."This means that the statement proffered to the intellect contains a contradiction within itself, so that no concept can be formed embodying the statement. A four-sided triangle, for instance, is inconceivable.... Thus the first test of any statement concerning spiritual reality is not can imagination from a mental picture of it, but does it stand up to the examination of the intellect, do the terms contradict each other.3Something similar happens in science. We all, no doubt, can remember being taught about molecules in high school science class with styrofoam balls and tooth picks. This was a learning tool designed to help us imagine molecules, but - the scientists remind us - molecules don't actually look like that. Scientists don't believe in a bunch of balls and sticks when they speak about molecules, rather they believe in the mathematical formulae that are merely represented by the foam ball models. The scientist can comprehend molecules without needing to or even being able to imagine them.
When Jefferson says the Trinity is "incomprehensible" he really means it is "unimaginable," which, of course, it is. That shouldn't surprise Jefferson however, nor should it undermine our Faith in a Triune God. In fact, it should bolster it. A "make believe" God would be an imaginable God, like the pagan gods of old. He would have an elephant's head or look like a perfect man or be presented in some other easily imagined way. Any such simplified version of God, should all be immediately suspect as possible human inventions. We'd expect the real God to be unimaginable precisely because He isn't a part of the material universe. We can't sense Him, therefore we shouldn't be able to imagine Him either.
All images of the Trinity must therefore fail. Apples, shamrocks, "another Cerberus with one body and three heads," all must be rejected out of hand as trying to imagine the unimaginable. We instead can only have the idea and, if it helps, a "model" much like the one used to teach non-scientists about molecules,
If you still need help understanding the doctrine (not imagining it), C.S. Lewis might help,
You know that in space you can move in three ways - to the left or right, backwards or forwards, up or down.... They are called the three Dimensions.... If you are using only one dimension, you could draw only a straight line. If you are using two, you could draw a figure: say, a square. And a square is made up of four lines. If you have three dimensions, you can then build what we call a solid body: say a cube... And a cube is made up of six squares.4
Each dimension, therefore builds off the previous ones. But, at the same time, if you or I were trapped in a two dimensional world (say we were cartoon characters) we couldn't even imagine a cube. We'd simply have no experience of such an object, no experience, in fact, of "solidity" at all. Thus, by definition we could never have a physical experience of such an object or, therefore, an image of one.
the Christian account of God involves just the same principle. The human level is a simple and rather empty level. On the human level one person is one being, and any two persons are two separate beings - just as, in two dimensions (say on a flat sheet of paper) one square is one figure, and any two squares are two separate figures. On the Divine level you still find personalities but up there you find them combined in new ways which we, who do not live on that level, cannot imagine. In God's dimension, so to speak, you find a being who is three Persons while remaining one Being, just a cube is six squares while remaining one cube.5Is it "complicated?" Yes, it is. But so is reality. Right now I'm sitting at a computer writing this blog post. That seems like a simple enough activity. But bring in a computer scientist to describe, in detail, all the various complex procedures and programs that my computer is running to write this, or all the more complex processes that lead to it being able to be published online and read by people around the world and it gets a bit more "complicated." Let the computer scientist be joined by a neuroscientist to tell us all about the electric discharges my brain makes use of to move my hands to type the words that express my thoughts (let alone all the unconscious mental processes that it simultaneously is performing to keep me alive) and we've got greater complexity still. Add a physicist to tell us how my body and computer are both managing to stay put on the Earth while I speed 67,000 mph around the center of the solar system and an electrical engineer to add his two cents in on how the computer is being powered and we've reach a level of maddening complexity. Should we, then, really expect the inner life of the All High God, the God who created this complex world, to be so very simple to understand? Shouldn't we rather expect religion, if it be true, to be one of the most complex subjects and the doctrine of the being of God to be the most complex of it's doctrines?
One of the greatest minds in the history of Christianity, St. Augustine of Hippo, spent more than three decades writing one of the greatest books on our subject, De Trinitate (On the Trinity). While writing it he had a very famous dream in which he encountered a small boy on the beach carrying water in a seashell from the sea and pouring it into a hole in the beach. The great saint asked the child what he was about. "Transferring all the water from the sea into this small hole." "Why that is impossible my boy." "As is what you are trying to do in your book." Tradition holds that this was a angel sent by God to remind the great saint that some mysteries are too much for the human mind to ever fully understand. In fact, a good test as to whether your idea of God is "made up" or not is this "seashell test." If you fully understand it, it isn't God.
That shouldn't reduce us to intellectual impotence or indifference. We can understand the Trinity, we can gain some light from the doctrine, but we shouldn't be surprised when our finite minds can't entirely contain the inner life of a "supra-personal" God. We shouldn't be surprised when imagination fails and the intellect can only begin to comprehend the mystery6. Rather we ought take comfort in knowing that we haven't made God in our image and likeness (despite our imagination's continual demands to reform Him so). Rather, He is something entirely unexpected.
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1. Jefferson, Thomas, Letter to James Smith 12/8/1822 (he must have been in the Christmas spirit)
2. The tradition of people, learned in subjects other than theology, thinking themselves master of this subject too is long and sad. People with little skill or training in religion or theology find themselves well qualified to speak on theology in a way no one would with any other discipline. Being a great statesman, like Jefferson, clearly doesn't make someone ipso facto a theologian. Such should be a lesson to biologists (Dawkins), physicists (Hawking), journalists (Hitchens), astronomers (Sagan), and others. Just as being a great biblical exegete or Thomistic philosopher wouldn't qualify one as an expert on human anatomy or neuroscience, so too being learned in other fields doesn't qualify oneself as an authority on philosophy, theology, or Biblical exegesis.
3. Sheed, Frank, Theology and Sanity, pgs. 31-36
4. Lewis, CS, Mere Christianity, pg 161
5. Lewis, CS, Mere Christianity, pg 162
6. In Christian theology the word "mystery" is used in a very different sense than it is in the secular world. Here we are not speaking of something Sherlock Holmes would "solve." It isn't a puzzle. Nor are we speaking of something that we simply have to accept without being able to understand anything at all about it. A "mystery" isn't a Christian way of "copping out" on having to be reasonable. A "mystery" in the sense we are using it here is simply something that has a dimension greater than what we know. It is something that goes beyond being entirely understood by the intellect, although it can be understood to a degree. For a great, short look at what Christians mean by "mystery" I highly recommend this post by Mgsr. Charles Pope: Mystery is Deep and Yet Vertical - A Brief Meditation on the Christian Meaning of Mystery.