321 begins by associating God with three-ness. "God is three Persons united in love" says the presentation. And occasionally people have asked, "What about God's one-ness?"
Well the short answer is - it's right there in the explanation: "three Persons united in love." That phrase is just trying to unpack the word Trinity which is itself only the squashing together of "tri" and "unity". Just from the word 'Trinity' it should be clear how the church has considered God's one-ness historically. God's one-ness is a unity of the Three. It's not a unity apart from the Three or underneath the Three. But often we think like that.
It's always revealing when people say things like: "Trinity is great but we also need to focus on God's unity." This is literally the same as saying "The unity of the Three is great, but we also need to talk about the unity of God." At that point we really need to ask, "What is this second kind of unity you want to talk about? And what is this God you want to talk about apart from discussion of the Three?" Those are worrying questions to raise!
To answer them, people sometimes try to wheel in Gregory of Nazianzen for support. In doing so they make him say the precise opposite of what he meant. Here's his famous quote:
No sooner do I conceive of the one than I am illumined by the splendour of the three; no sooner do I distinguish them than I am carried back to the one.
Wonderful theology. Yet in a heartbeat the thought can get turned into...
Once I've spent a decent amount of time thinking about the one God of monotheism, I then force myself to spend the same amount of time considering Father, Son and Spirit. And once I've given equal airtime to the Three, I return to my philosophically defined monad.
But that couldn't be further from Gregory's meaning. The One simply is the profound interpenetration of the Three and the Three just are 'in' each other in unloseable, mutually-constituting, ontological oneness. Gregory is not saying that we ought not to think of one-ness and three-ness separately. He's saying we cannot do it. The one and the three are strictly mutually-defining concepts.
Yet every time someone says "Let's not prioritise trinity, let's give equal time to the unity" they attempt this feat. Whatever three-ness they're considering apart from the one-ness - it's not the true three-ness of God. Whatever one-ness they're considering apart from the three-ness - it's not the true one-ness of God.
So here's my offer. I will happily major on the one-ness of God for the rest of my life. I will rename the website one-two-one.org - cool, still has a nice ring to it. But I'll do it on one condition: can we please all agree that this oneness is the one-ness of Jesus with His Father?
You see, if we're talking about Christ, if we're talking about the gospel, if we're talking about salvation, then whatever one-ness we uphold must not destroy the concrete Person of Jesus. It must not mess with the gospel economy in which the Son lives and dies before the Father, is exalted and ministers before Him. It must not dissolve our salvation in which the Son bears us before the Father. If Jesus, if the gospel, if salvation determines our God-talk then the one-ness we maintain must be a one-ness of distinct Persons mustn't it? It must be a one-ness that includes difference and interplay and relationship mustn't it?
So if the one-ness we're talking about is the "one-ness" of Jesus with His Father then sign me up. I couldn't be more for "one-ness". I'll talk about this one-ness until Jesus returns. But some want to talk about another one-ness - a one-ness that would dissolve the Person of Jesus, His gospel, His salvation. A one-ness that would involve not merely looking away from 'the Three' in some abstract sense, but looking away from Jesus and His gospel in order to know God. To look to this other one-ness is to look away from the God of Jesus and we must never do that.
There can be only one kind of one-ness. And it's the one-ness of the Three.