“The idea of God, as the church fathers generally recognized, must be largely given over to mystery. Augustine said that we speak of the Trinity, not because we can explain this mystery, but only in order ‘not to be silent’ and allow greater error.” (41)
I found this statement by A.J. Conyers in A Basic Christian Theology to be quite fascinating. In one sense Conyers is exactly right. How do we explain three-in-one? It doesn’t even make logical sense that something could be both three things and one thing at the same time. The church fathers settled on the statement that God is of one ousia (substance) and three hypostasis (persons). One of the guys in my midweek study had a good illustration for this concept. He pointed out the different states of water and the parallel to our thinking on the Trinity. Water can take on the form of liquid, solid, or gas. Each form has distinctive features so that liquid is not the same as gas. However, they all carry the same basic substance: water. I think his illustration is a good parallel to the Trinity. God exists in three distinctions but all of these distinctions are comprised of one substance. As Conyers says, it is a great mystery. Yet the mystery of it all does not keep us from saying something about who God is. If it did, there would be no way to combat error or false teaching.
In another sense, Augustine’s quote is a bit narrow. We do not merely speak of the Trinity for the sake of combating false teaching (though this is important). We speak of a triune God because he has revealed himself in this manner. And God has revealed himself in this way because he exists in this manner. We must be careful not to make the same mistake that Sabellius made in thinking that God reveals himself by putting on three different masks though he is only one person. Scripture does not give us this picture of God. We also speak of the Trinity because God is actively working as each person though in different ways. The Spirit resides within us and guides us toward holiness. The Son intercedes on our behalf at the right hand of the Father who sits on the throne of righteousness.
Nevertheless, another one of the guys in my study said that this quote could also be representative of our pursuit of theology. There will never be a point when we will know exhaustively. There will always be some sense of mystery because there are things we do not understand. Yet we study theology so that we might be drawn closer to God, be transformed as a result, and learn to speak as representatives of His kingdom.