Why Christian Symbolism Is Inadequate for Describing the Holy Trinity
“O the depth of the riches both of the wisdom and knowledge of God!
How unsearchable are His judgments, and His ways past finding out!”
—Romans 11:33
“The Lord, He is God; there is none else beside Him” (Deuteronomy 4:35). “There is none other God but one” (I Corinthians 8:4). In unmistakable terms the Scriptures declare that there is only one God. Likewise, with equally clear words, the Bible also tells us that there are three divine persons in the Godhead—“the Father,” “the Son,” and “the Holy Ghost” (Matthew 28:19). The Father is clearly identified as the one true God (John 17:3); the Son is clearly identified as the one true God (John 1:1–3, 14); and the Holy Ghost is clearly identified as the one true God (Acts 5:3–4). And while the essence of the Father, Son, and Holy Ghost is “one” (John 10:30; I John 5:7), each is a distinct person, or Individual (John 14:16; 15:26). In Romans 11:33 (quoted above), which is part of the Epistle Lesson for Trinity Sunday in the historic pericope, we are told that God’s wisdom and knowledge are infinitely deep, and that His judgments and ways exceed man’s ability to comprehend. But not only is it impossible for us humans to fathom the Lord’s wisdom, knowledge, judgments, and ways, it is also impossible for us to grasp intellectually how the one true God is three distinct Persons (Father, Son, and Holy Ghost), with each person being fully God (not one-third of God).
When something is hard to understand, we humans typically seek a comparison that is easier to grasp; and then, using the parallel aspects, we make the mental connections to comprehend that which is more difficult. But analogies are not always completely accurate in their comparisons. They often oversimplify things; and sometimes they add unnecessary complexity to a matter—making it all the more confusing. Now when it comes to an explanation of our Triune God, we have to admit that, apart from Holy Scripture, there is no explanation, because “the things of the Spirit of God…are spiritually discerned” (I Corinthians 2:14). Therefore finding even an analogy or imperfect illustration of the Trinity does not cause us to understand it. In addition to the fact that we cannot accurately picture something that has no physical form, we also cannot hope to picture how the Godhead is three persons in one being. The personal beings that we are most familiar with are humans; and we cannot even think about three distinct human persons without also thinking about three separate human beings. There is absolutely nothing else in the entire universe that matches the uniqueness of the Trinity. Because it is impossible for us to conceptualize how the three distinct persons (Father, Son, and Holy Ghost) are each the one same divine being, it is also impossible for us to find a perfectly adequate picture or symbol for the Trinity. Based on this fact, some might think that it is foolish to use any symbols at all to represent the Holy Trinity. However, even imperfect symbols, illustrations, and analogies can be profitably used as long as their limitations are recognized, and their use does not in any way conflict with the express words of Holy Scripture.
Perhaps the most common symbol for the Trinity is the triangle—one shape with three corners (also three sides). The single shape of the triangle is compared to the oneness of the divine essence; and the three corners (or sides) are related to the three persons in the Godhead. Similarly, the three-leaf clover has been used for the same basic reasons as the triangle. All symbols of this type share the same basic shortcoming: The three parts that make up the shape are not each the entire shape, but only parts of the shape. So if the entire shape represents God, and the three parts represent the Father, Son, and Holy Ghost, then each divine person is pictured as being only part of God. It is the same problem that arises more conspicuously if one tries to illustrate the Trinity with a pie chart divided into three segments—neither the Father, nor the Son, nor the Holy Ghost would appear to be fully God, but only thirds of God.
A symbol of three interlocking circles is sometimes used to represent our Triune God. One theological point that is illustrated with this particular symbol is the interpenetration (perichoresis) of the divine persons (John 17:21). (This interpenetration is also symbolized in the “triquetra,” which is sometimes called the Celtic “Trinity knot.”) A circle all by itself is often used as a symbol for God with special reference to His attribute of eternity (without beginning and without end). Now if the entire shape formed by the interlocking circles is to represent the one divine being, then this symbol suffers from the same shortcoming as the three-piece pie chart. 
If, on the other hand, each circle by itself is to represent God (the divine essence, not specifically one divine person), then the symbol would indicate that there are three eternal beings instead of one. While it is correct to say that each of the three persons is eternal, it is wrong to say that there are three Eternals (which would mean that there are three Gods). “The Father eternal, the Son eternal, and the Holy Ghost eternal. And yet they are not three Eternals, but one Eternal” (Athanasian Creed).
Just a brief note about a modern kind of geometric image that some have thought to be a good example of the Trinity—fractals: This has been suggested as a solution to the pie chart problem found in the triangle and similar symbols, because, it is claimed, that the parts are the whole. (In reality, the parts are only copies of the whole.) Fractals are, in fact, one of the worst of symbols for the Trinity, because their composition would imply that there are an infinite number of gods (or divine persons) within God.
There is actually quite a good illustration of the Trinity at the top of page 49 in the 1943 edition of Luther’s Small Catechism (C.P. H.). It is an English version of an old Latin illustration called “Scutum Fidei” (“Shield of Faith”) that dates back to the 1200s (or earlier). What makes this picture more than just a symbol is the use of words within the image. It is really a series of verbal statements about the persons of the Trinity grouped together in an artistic way. Since the graphic in the Catechism is small, the words (which are necessary to understand it) may be a little difficult to read. The symbol part displays a shield-like shape with four circles (three on the outside and one in the center), and connecting lines that run between the circles. The three outside circles contain the names of the three divine persons (one name in each circle); and “God” is written in the single circle in the middle. The words in the lines, taken together with those in the circles, set forth Scriptural statements regarding each person of the Trinity. If there were no words present, this illustration would not be very good (and could easily be misunderstood); but the words in the circles and in the lines clearly explain the distinction of persons as well as the unity of essence in the Triune God—“neither confounding the persons nor dividing the substance” (Athanasian Creed).
With words we can describe the Trinity accurately, for it is with words that God has perfectly revealed Himself to us on the pages of Holy Scripture. But even though we can describe the Trinity correctly, this does not mean that we can visualize, illustrate, or even comprehend how Father, Son, and Holy Ghost can be distinct persons who are each fully God, without there being more than one God. It should not be surprising that no symbol can be found—no geometric object, no mathematical formula, no example in nature, no artistic representation—that accurately parallels or illustrates the mystery of the Holy Trinity. God is so unique, and so beyond our ability to comprehend, that there is nothing else we can point to and say, “The Trinity is just like this or that.” It does not follow, however, that no symbolism should ever be used in teaching about the Trinity, or that all triangles and triple interlocking circles should be removed from our churches simply because they do not represent every aspect of the Trinity with complete accuracy. But when teaching about the Trinity using symbols, care must be taken not to go beyond the legitimate points of comparison in trying to establish parallels.
Even with the perfect parables of Christ, there may be ancillary details in the illustrations that Jesus Himself does not make a part of His point of comparison. Consequently, we must be careful not to attribute significance to details in a parable that lie beyond the point of comparison stated or otherwise clearly drawn by the Lord. If such care is not taken, completely wrong ideas may arise. For example, in the Parable of the Wise and Foolish Virgins (Matthew 25:1–13), ten virgins with their lamps waited together in anticipation of the bridegroom’s arrival. Five were wise in having brought an extra supply of oil for their lamps in anticipation of a long wait, while five were foolish, having brought no extra oil with their lamps. Nevertheless, all ten virgins “slumbered and slept” (v. 5). The coming of the groom represents the coming of Christ on the Last Day. But it would be wrong for one to say that this parable teaches that, upon the Lord’s return for judgment, the number of those who by faith are admitted into heaven will equal the number of those who in unbelief are consigned to hell. Such a conclusion disregards the fact that the number (and ratio) of wise and foolish virgins is a detail that is unrelated to the main point of the parable, namely, that only true believers, who by faith nurtured by the Means of Grace are ready for Christ’s second coming, will be admitted into heaven (v. 13). Likewise, in the Parable of the Unjust Judge (Luke 18:2–5), the effectiveness of persistent prayer is illustrated by the widow’s persistent petitioning of the unjust judge to help her (see verses 1 and 7). But it would be wrong to say that this parable teaches that God is unjust or that He is wearied by many prayers. Simply because not every detail of a given parable can be directly connected with the main point does not render the parable useless or detrimental to the proper understanding of the lesson that the parable teaches.
While humanly devised symbols or illustrations are not worthy to be placed on the same level as the parables given us by God, and while there may be a number of details in the analogies we humans invent that do not perfectly illustrate our point, such analogies, symbols, and illustrations can be used profitably in explaining even points of Christian doctrine, provided that they do not conflict with or go beyond Scripture. Accordingly, illustrating the Trinity with a triangle can certainly be done in a profitable way as long as the details that lie beyond the legitimate points of comparison are not allowed to detract from what Scripture clearly teaches. The parts of the illustration that do not accurately represent the Trinity might well be highlighted for the purpose of explaining what our Triune God is not. In fact, a good way to present the substance of any matter thoroughly is to include a clear explanation of what it is not. For example, a teacher of religion might tell his student: “Like a triangle is a single shape, so also God is one single being; and like there are three corners (or three sides) in a triangle, there are three persons in the Godhead. But unlike the corners (or sides) of a triangle, which are only parts of the shape, each divine person is completely God—not a part of God.”
So if one desires to teach others accurately about the Triune God, he may or may not choose to use some symbolism; but he absolutely must use accurate words to describe the Trinity according to how God has revealed Himself in the Bible and thus overcome the inadequacies of any symbols he might use. As with all the doctrines of Holy Scripture, we are to believe, teach, and confess whatever has been revealed therein; and this holds true whether or not we are able fully to comprehend those doctrines which are mysterious (I Corinthians 13:12). The fact that we know of no symbol or analogy that perfectly illustrates the Bible’s description of the Trinity should not lead us to conclude that this doctrine, though admittedly a mystery, cannot be taught or explained or believed. However, the doctrine of the Trinity should humble us before the Lord our God and cause us to acknowledge His transcending uniqueness, as well as our very limited mental abilities. It really should not disturb us or surprise us at all that the essence of God is as incomprehensible as are His mind, wisdom, knowledge, judgments, and ways. Let us, therefore, stand in awe before the Lord and declare with the Apostle Paul: “O the depth of the riches both of the wisdom and knowledge of God! How unsearchable are His judgments and His ways past finding out! For who hath known the mind of the Lord, or who hath been His counselor?” (Romans 11:33–34).
—P. E. B.