You may have heard someone suggest that the Christian doctrine of the Trinity — and specifically belief in the deity of Christ — only came about as a result of a conceptual tangle. People who argue this, think that the Christian belief in Jesus as God is an unintended side-effect of transplanting an essentially Jewish message — about the Jewish Messiah (‘the Christ’ or ‘Son of God’) — into Greek philosophical soil.
On this view, when Christians declare (in the words of the Nicene Creed) that Jesus is ‘of one Being with the Father’, they’re betraying the New Testament story of Jesus. Worse, they’re allowing philosophy — mere human guesswork — to take centre stage, shunting what God has revealed about himself off to one side.
What’s interesting is that the fourth-century Christians who opposed Nicene-style theology also felt like this. They objected to the key word homoousios — which was drawn from Greek philosophy and meant something like ‘one being’ or ‘the same substance’. To them, this implied that God was something physical like Coca Cola — a liquid that could be poured into different bottles. Either that or something worse — like the idea that God was really a nameless and unknowable oneness which simply wore the different ‘masks’ of Father, Son and Spirit as necessary.
These fourth century Christians rightly worried about both of these ways of picturing it, sensing that they created big problems. Problems like: How can we know we’re really in touch with the real God when we’re dealing with Jesus and the Spirit? How can we know that each bottle contains the same liquid? How can we know we’re actually connected with God if all we see are masks?
But the defenders of Nicene theology replied: ‘This is exactly what the word homoousios is meant to safeguard! It acknowledges Christ’s genuine identity with the one and only God.’
This Greek word (of dubious heritage) is supposed to help us do justice to what we see in the New Testament story. It assures us that we know we’re really in contact with God when we’re dealing with Jesus and the Spirit precisely because they share in one being.