Review of the Trinity

Trinity Error Triangle


As you will know Mike Beck and I have recently been to India to teach at the Coonoor Theological Studies group that happens every year. It was a great time and we taught on theological topics. Mike taught on the Two Adams examining the covenantal structure of revelation. I taught on the Trinity. The teachings were very well received and I wanted to share with you just two parts of the teaching which I thought helped the students the most. I hope these will refresh and clarify this wonderful doctrine for you as well.

The error triangle

Let’s begin by giving a definition of the Trinity. What is your definition? Here is a helpful one that can be used to think through the doctrine more usefully. We believe in God in three persons who are all co-equal and co-eternal. There are 3 main ingredients to this definition. We believe in one God which confesses the monotheistic base of the teaching, but this one God exists not as one person like every created creature we have encountered but three persons, here we emphasise the tri-personal nature of God. And each of the persons is co-eternal and co-equal, there is none of the 3 which are less eternal or less equal in their divine natures. This definition is helpful when used in the form of the error triangle.

Trinity Error Triangle

You will notice that the 3 parts of the trinity are mentioned and then at the 3 corners of the triangles there are certain errors mentioned. This triangle illustrates that if you deny any one of these three truths you will follow the coinciding angles of the triangle into error. So if you hold to three persons who are equal but deny monotheism you end up with polytheism. If you hold to monotheism and 3 persons but deny they are all equal you end up in subordinationism. And if you believe in monotheism and equality but deny three persons you become a Modalist. This model teaches us to hold these three truths in tension.

Holding these three truths in tension is not an imposition on the bible but the only way we can honour the bible’s teaching on who God is. We clearly see three eternal persons who have a divine nature. Since God’s word teaches it we are obliged to honour the revealed facts and not hold them in such a way as to deny them. The three distinct persons can be seen at Christ’s baptism. That they are all eternal is seen in Heb. 9:14, Jn. 8:58, Mic. 5:2, Ps. 90:2.

The law of non-contradiction

We used R. C. Sproul’s little boom on the Trinity and in it he shares a helpful way to think about the Trinity as not being a contradiction. ‘Others see the Trinity as the church’s retreat into contradiction. For instance, I once had a conversation with a man who had a PhD in philosophy, and he objected to Christianity on the grounds that the doctrine of the Trinity represented a manifest contradiction—the idea that one can also be three—at the heart of the Christian faith. Apparently this professor of philosophy was not familiar with the law of non-contradiction. That law states, “A cannot be A and non-A at the same time and in the same relationship.” When we confess our faith in the Trinity, we affirm that God is one in essence and three in person. Thus, God is one in A and three in B. If we said that He is one in essence and three in essence, that would be a contradiction. If we said He is one in person and three in person, that also would be a contradiction. But as mysterious as the Trinity is, perhaps even above and beyond our capacity to understand it in its fullness, the historic formula is not a contradiction.’ God is one in a different way that He is three, this is mysterious but it is not a contradiction.