Christians believe in one God who is Trinity. One God in three Persons. Oneness in Threeness. Unity in Difference. Of course, this may all seem to be quite strange, contradictory, or just plain nonsensical. How can something be one thing and three things at the same time? Normally we would say that it is only possible if the three are considered parts of the one, or of a different category. But Christians want to say that the three “aspects” of God are not parts. Each is fully God yet cannot exist alone without the others. In this Christian mathematics it seems possible that 1 + 1 + 1 = 1.
This has led many to throughout the ages to reject the Christian doctrine that God is a Trinity as absurd. However, when you come to understand what the early Christians were saying, these rejections come to appear unfounded. In fact, I have come to see the belief as incredibly profound and beautiful.
It makes all the difference when you realize that the early Christians who explained the Trinity believed that God is ultimately above counting. All our language is ultimately inadequate to speak about what God actually is, since all language is from and of the created world, and God is the sole uncreated reality. He is not a thing among things in the world. He is in a category completely of his own. As created beings, we are bound within the category of created things. We cannot get outside of those boundaries to look at or talk about what is uncreated. Nonetheless, we have to use language and concepts from the category of created things to talk about something else entirely, the Uncreated One. The language from the first category will always be inadequate to talk about the second one. This does not mean that what we say about God is not true. It certainly is. But it will never quite “get there.” Our words and concepts have to point like signposts to something out beyond their capability of expression.
So what does this have to do with the Trinity? Number and counting are something that belong to the created world. God is beyond what we can describe with these concepts. He is beyond counting. He is in a category completely to his own. There is ultimately nothing that can be counted alongside him. Numbers as counting things do not make sense in reference to God. He is One, Oneness, Unity. He is Three, Threeness, Difference. But he is not one or three in the sense that we can count a series: 1, 2, 3, etc. One and three in reference to God are pointing towards an outer darkness where those concepts cannot penetrate: signposts pointing to an ultimate reality beyond our comprehension.
When you begin to understand God this way, all the criticisms against the Trinity just kind of melt away. Generally, the people who make them are talking past the doctrine of the Trinity, and therefore the critiques are not applicable.
The doctrine of the Trinity then ultimately points to God as perfect unity that is in no way diminished or distorted by difference. There is nothing in the world like this. But God is beyond there world, and our words and concepts cannot quite reach him. Again, he is ultimately unlike anything in the world, even though all things bear traces of him.
But what is the practical significance?
I think that everything depends on it.
The Trinity means that God is in his core both sharing and receiving—perfect love. The Father, the Source of all divinity, eternally and perfectly shares everything he is with the Son in an eternal, dynamic procession. The Father gives himself in his entirety to the Son. And the Son in gratitude eternally receives the fullness of the Father’s being. And this love that shares and this love that receives overabounds as God’s Spirit.
To summarize, the basis of the Trinity is that God is eternally-overflowing, abundantly self-giving, joyfully-receiving love.
Secondly, the Father wholly gives himself and the Son receives with no diminution from the Father. I think this points to a glorious spiritual reality. In opposition to our material existence, where for me to share with another means I must diminish my material wealth, the world of spirit is different. Spirit has nothing to do with laws of supply and demand or principles of scarcity. For whoever seeks it, it is there in plenitude. No lack. Spirit is always free and on offer to all people of all classes, ethnicities, and walks of life. The school of the Spirit is available free of cost, at all times and places to all who will enroll. And wealth of spirit is something that we never need to compete with one another over but only rejoice in as we grow into the fullness of the Divine Spirit.