A belated thought for Trinity Sunday...
In recent weeks, one question that has been revolving around my mind has been this: can we, in our own voices as 21st century Christians, recite the Nicene Creed? As a Christian with some concern for both catholicity and orthodoxy, that the question should occur at all is worrying. I've been led to it by arguably the most important clause, which declares that the Lord Jesus Christ is "of one substance with the Father" - that is to say, homoousios. The significance of this word for the debates over Trinitarian theology in the fourth century, and therefore for all subsequent Christian thinking, can hardly be overstated. This was, ultimately, the dividing line between the Nicene party, which was eventually triumphant as the standard of Christian orthodoxy, and the Arian heresy and all those who would compromise with it. It really matters. It answers the question 'is Jesus really God?' with an emphatic yes.
So why might we not be able to say it with our own voices?
The problem is that the Nicene definition operates within a particular metaphysical view of the world which is alien to us. The idea of 'substance', which lies at the heart of the debate, is just not one that exists in contemporary ontology. The language of three 'persons' 'subsisting' within one 'substance' is alien to us. I'm not at all suggesting that we should ditch the creed; we can understand it, if we do the work, and we can understand what was meant by it and why it mattered and therefore continues to matter. We can (and should) say it in their voices, or perhaps in the voice of the church universal, but I don't think we can say it in our voices. I don't think that indicates a fundamental problem; the metaphysics in which the Trinitarian dogma was expressed was never drawn from the gospel. It was the scaffolding, and if that scaffolding no longer works for us, we can move on, albeit maintaining the appropriate respect for the language in which the essential truth has been communicated and safeguarded in the past.
The question, really, is 'how do express this truth in a post-metaphysical age?' How do we say it in our voices?
I do think it's something we need to think about. The threat of a bald monotheism is always lurking, where Father, Son and Holy Spirit disappear into the mush of an undifferentiated godhead. And then the gospel becomes impossible; the story makes no sense without these characters. However, the bigger issue on my mind at the moment is how we avoid tritheism. I've heard a number of people teaching on the subject of the Trinity in a way which, to my mind, does not adequately guard against this danger - perhaps because more effort is going into watching the other door to ensure monotheism doesn't sneak in. Still, it is not sufficient to say that Father, Son and Holy Spirit are one because of their relationships; social Trinitarianism is built on an overly-literalistic (and anachronistic) interpretation of the word 'person'. Three persons in relationship is true but insufficient as an expression of the unity of God. Also, any system which can allow God to be described as a 'committee' - I have heard this taught - is wide open to tritheism, if it is not already in the middle of it.
So my question is, if 'substance' doesn't work for us, how do we say 'God is One' in a way which will shut out tritheism fully and finally whilst allowing the telling of the gospel story with all its inter-Trinitarian interactions?