Introduction to the Tri-unity of God

Originally posted on 4/14/2020

From the very beginning of Christianity, certain doctrines have been held in special reverence by Christians everywhere. Even though the differences between Christian denominations, sects, and traditions are vast, it remains true that certain essential doctrines hold us altogether. One of those doctrines is the Trinity. Those Christians that appeal to the Bible as authoritative, all agree that one must accept the doctrine of the Trinity for one to be a Christian. This is one of those special areas where all Christians see eye to eye. If you do not believe in the Trinity, then you cannot be a Christian. It is as simple as that.[i]

Depending what Christian tradition you follow you may, or may not, use creeds in your worship service. The word "creed" comes from the Latin credo meaning "I believe." The creeds are considered concise statements concerning what must be believed in order to be a Christian. They were written in times of low literacy to be memorized so that the average Christian could understand their faith.

Almost all mainstream Christian traditions accept at least one of the following creeds as true, even if creeds are not used in their normal worship services: The Apostles Creed, the Nicene Creed, and the Athanasian Creed. Oh, it is certainly true that there are some arguments about how certain phrases should be translated and what version of a particular creed should be used. Some traditions accept all three creeds; some accept only one. Still, arguments about wording and translation notwithstanding, it is generally conceded that at least one of these creeds is an accurate description of the Christian faith.

Even though these creeds were written at different times to address different problems, all three have one thing in common: They all make direct statements affirming the doctrine of the Trinity.  Both the Apostles Creed and the Nicene Creed are divided into three sections. The first section expresses belief about God the Father, the second speaks of Jesus his Son, and the third refers to the Holy Spirit. The third Creed, the Athanasian Creed, while not following this general outline, speaks almost exclusively about the nature of the Trinity. 

The fact that all three of these creeds speak in one way or another of the Trinity and that at least one of them is accepted by all of Christianity shows how important the doctrine of the Trinity is. The doctrine of the Trinity is not merely for those with theology degrees. It isn't for a special brand of Christianity. No, the doctrine of the Trinity was included in those statements of faith intended to teach the essentials of the faith to all Christians everywhere.

What this means is that every person who is born again should have at least a general understanding of the Trinity. This is particularly true if one is making a more intense study of the person of God himself.

Knowing More Than We Can Tell

As an experiment, I recently asked a young woman to describe her 5-year-old daughter’s face. This evidently delighted the young mother as a big smile appeared and her eyes beamed. She eagerly took up the challenge. She told me that her daughter's face was roundish with puffy cheeks, that her ears were somewhat pointed, that she had dark eyebrows and brown eyes, and that the bridge of her nose was somewhat narrow. I asked for more details, and learned a few more particulars. But I noticed a frown gradually replacing her smile. As I pressed for more information, frustration set in. Eventually she gave up with a shrug and a sheepish grin, saying, "I don't know what else to tell you." 

To be clear, she knew what her daughter looked like. She had the information. In fact, I would venture that she had more biometric data on her daughter's face than the best facial recognition software could provide. What she didn't have was the ability to communicate that specific information. Oh, she was able to express certain generalities about her daughter, but not enough so that I would be able to pick her out on a playground. It’s clear that she knew more than she could tell.[ii]

Knowing more than we can tell is an affliction we all experience in numerous areas of life. Here is another example of this problem. We all know what we mean by “time.” We experience it every day. But try to define it! It may surprise you to know that even the most advanced physicists struggle to define time. We experience it, but we cannot define it.

Which brings us to the subject of the Trinity, or as I prefer to say it, the tri-unity of God. I am convinced that all believers are immersed in the tri-unity of God from the moment they put their faith in Jesus Christ. Oh, they might not be able to expressly state the orthodox doctrine of the Trinity — that there is one God, eternally existing in three persons, whose substance cannot be divided and whose persons must not be confused. But they know something about the tri-unity of God. In fact, I consider it highly likely that they know more than they can say.

This is not to say that they will always put the information they possess together in a correct manner. When I was a new pastor at my very first church, I had a lovely young lady in Sunday school talk about "God the Father who became God the Son who became God the Holy Spirit." I immediately stopped my lesson and politely asked how many in the class thought this was a correct statement. Over half the class (including the chairman of the Sunday school department) raised their hands. I immediately stopped my prepared lesson and held an impromptu study of the tri-unity of God to correct this error. Still, everyone there knew something about the tri-unity of God, even if they couldn't put the facts they held into a correct form.

To come to God in saving faith, one must know that Jesus is God and that he died for our sins. We learn early on that "God so loved the world that he gave his only begotten son…" (John 3:16). At our baptism we hear the words intoned "in the name of the Father, and of the Son, and of the Holy Spirit. Amen." We learn at Christmas that the Holy Spirit overshadowed the Virgin Mary and conceived in her womb the baby Jesus. On Good Friday we hear Jesus (whom we know to be God) cry out from the cross, "My God, my God, why have you forsaken me?" (Mark 15:34). As we dig deeper into the Gospels, we see the Holy Spirit descending upon Jesus like a dove, while God speaks from heaven, “You are my Son, whom I love; with you I am well pleased” (Mark 1:11). We might not know what to make of all this; we might not be able to express what we know, but we all have an almost unconscious knowledge of the tri-unity of God.

I think we all will admit that this kind of knowledge about the tri-unity of God is good, but not nearly good enough. After all, dealing with the tri-unity of God, even at the best of times, is a difficult business. But when all you have are several fuzzy, and seemingly incompatible, ideas about the tri-unity of God, frustration quickly sets in. Nicky Cruz, former gang leader turned evangelist,[iii] describes this frustration with learning about the tri-unity of God.

I didn't understand it. I believed it was true, though at first only because I had such great confidence in those who taught it to me. Then later I believed it was true because I saw it to be true in the Bible. I saw, over and over, the clear teaching in Scripture of these three faces of God. So I believed it, but I still did not understand it. And, since I could not understand it, I wondered why God made it all so confusing!

Why have three persons, I thought, when it confuses me so much? It seemed to me such a totally unnecessary complication. Why couldn't God just be God? Then I can understand Him. This "Trinity" business I accepted by faith, but I could not relate to it at all.[iv]

 Many Christians, I fear, share this sentiment. Why does God have to be so hard? Why can't he just be like everyone else? Why does he have to be so different? Why does he have to be so… so… incomprehensible?

The answer to these questions becomes obvious when you state the problem out loud. God is who he is because this is what God is like. He can be nothing less. He will not become less than he is to make himself easier for us to understand. It's like my Great Dane asking me, "why can't you become a dog so that we can better relate to one another? After all, I find you so confusing." 

God desires that we find our delight in him as he really is. The first and greatest commandment is that we love the Lord our God with all our hearts and with all our souls and with all our strength (Deut 6:5; Matt 22:37). In contrast to this, the most fundamental sin is to try to change God into something he is not.

For although they knew God, they neither glorified him as God nor gave thanks to him, but their thinking became futile and their foolish hearts were darkened. Although they claimed to be wise, they became fools and exchanged the glory of the immortal God for images made to look like mortal man and birds and animals and reptiles. Rom 1:21-23

 Loving God as he actually is, as opposed to changing him into something we like better, requires faith. God is so different than we are. While he has created the cosmos (the matter, energy, space, and time in which we live), he remains separate from all that he has created. As a result, we who are part of that creation cannot work our way to him. He must reveal himself to us. As God reveals himself to us, we learn that he is "majestic in holiness, awesome in glory, working wonders" (Exod 15:10). Truly, there is no one like God. And therein lies a problem.

In chapter four we learned that God is at once incomprehensible and knowable. He is incomprehensible because we have never experienced a being like God. He is knowable because he has chosen to reveal himself to us. This is why, when we try to describe God, language so often fails us. We know more than we can tell, or at least more than we can put together in a way that seems logical to us.

In no place is the tension between incomprehensibility and knowability more obvious than in a discussion of the tri-unity of God. On the one hand, certain facts about God have been clearly revealed and are therefore knowable. On the other hand, our ability to reconcile these truths into some coherent picture is completely nonexistent. The tri-unity of God is an enigma that is frankly beyond our grasp. The best we can do is to state those truths that have been revealed and say, "God, in his greatness, is beyond my ability to comprehend."

The Limitation of Language

Compounding our problem with the tri-unity of God is the difficulty of the limitations of language. The word "Trinity,” for example, is not a biblical word. It is an invented word we use to describe the picture Scripture presents of God. I use the word tri-unity instead of Trinity, simply because I think it is better at communicating the difficult truth that must be understood. But it isn't found in the Bible either.

In the same way, the words "substance," "essence,” and “person" are also not found in the Bible to describe the tri-unity of God. They are primarily used because the early church father Tertullian (circa 150-225), who coined the word "Trinity" and was the first church father to tackle the tri-unity of God in detail, used them.[v] But his description has stood the test of time because we just can't seem to come up with anything better.

A Preliminary Definition

For this discussion I am assuming that the reader has at least some idea of what is meant by the term "Trinity." Just to be clear, the doctrine of the Trinity teaches that there is one, and only one God. This one God has eternally existed in three persons — The Father, the Son, and the Holy Spirit. These three persons share the same essence so that there is only one God. Yet these persons are distinct from one another so that the Father is not the Son, the Son is not the Spirit, and the Spirit is not the Father.

A more concise definition is provided by B. B. Warfield:

"The doctrine that there is one only and true God, but in the unity of the Godhead there are three coeternal and coequal Persons, the same in substance but distinct in subsistence [i.e. being or existence]."[vi] B. B. Warfield

The Nature of the Biblical Evidence

Hodge argues (correctly) that there is no one passage that one may turn to that “adequately” proves the doctrine of the Trinity. 

No such doctrine as that of the Trinity can be adequately proved by any citation of Scriptural passages. Its constituent elements are brought into view, some in one place, and some in another. The unity of the Divine Being; the true and equal divinity of the Father, Son, and Spirit; their distinct personality; the relation in which they stand one to the other, and to the Church and the world, are not presented in a doctrinal formula in the Word of God, but the several constituent elements of the doctrine are asserted, or assumed, over and over, from the beginning to the end of the Bible. It is, therefore, by proving these elements separately, that the whole doctrine can be most satisfactorily established. [vii]

In other words, the biblical evidence for the tri-unity of God is something like a jigsaw puzzle. We find one piece here, another over there, a third somewhere else.  No one passage gives us entire picture or the complete doctrine. We are required to fit each piece of evidence together with the rest in order to get complete picture.

When we examine the scriptural evidence for the tri-unity of God, we quickly discover that this evidence takes two tracks. One track emphasizes the unity of God. The other emphasizes the plurality, or the threeness, of God. The majority (but not all) of the evidence for the unity of God is found in the OT, while the majority (but again not all) of the evidence for the threeness of God is found in the NT. 

So, in the next chapter, we will look at each line of evidence in turn. 

[i] Oneness Pentecostals, for example, believe many true things essential to the Christian faith. But their rejection of the Trinity (among other things, including their view of salvation) places them outside orthodox Christianity. For a through examination of this movement, see Gregory A. Boyd, Oneness Pentecostals and the Trinity (Baker Publishing Group, 1992).

[ii] Michael Polanyi (1891-1976) coined the phrase "we know more than we can tell." (Michael Polanyi, The Tacit Dimension (Chicago: University of Chicago, 2009), 4.) According to Polanyi, there are at least two types of knowledge a person may possess: explicit knowledge and tacit knowledge. Explicit knowledge is information that is easily transferable from one person to another. The fact that the war of Jenkin’s ear was fought between Britain and Spain from 1739 to 1748 is explicit knowledge. It may be written down, transmitted, and understood by another. In contrast, tacit knowledge is knowledge which is possessed, but difficult to transfer to other people. Knowing how to draw a still life, cook with just enough — but not too much — salt, hit a baseball or tell a joke in a way that makes others laugh are all examples of tacit knowledge. So is knowing a person's face or the sound of their voice. Even the ability of transferring our thoughts to language is tacit knowledge. You know how to do it, but you won't be able to explain how. All of the above are cases of knowing more than we can tell.

[iii] You may read about Nicky Cruz’s exciting story and conversion in David Wilkerson, The Cross and the Switchblade (np: Jove Publishing, 1962).

[iv] Nicky Cruz, The Magnificent Three (Old Tappan, NJ: Fleming H. Revell, 1976), 15.

[v] Tertullian, “Against Praxeas” in The Ante-Nicene Fathers, vol 3, Latin Christianity: Its Founder, Tertullian (Peabody, MA: Hendrickson, 1999), 597-628.

[vi] Benjamin Breckinridge Warfield, Biblical and Theological Studies, ed Samuel G. Craig (Philadelphia: Presbyterian & Reformed, 1952), 22.

[vii] Charles Hodge, Systematic Theology, vol. 1 (Grand Rapids: Eerdmans, 1997), 446.