The astonishing thing that is announced at Christmas and becomes conspicuous at the cross is that God the Son has added to himself a complete, real, personal human nature. It’s his as much as yours is yours. And in that nature he, the eternal Son, experiences growth, suffering, death, and alienation, not to have a new kind of adventure but in order to put on our situation and save us in it. The hypostatic union means that he is always himself, is really God and really becomes really human.
I’m no Bible Answer Man or anything, but I get a lot of questions around Easter time.
How can God be unchanging if the Son became Jesus?
What happened to the Trinity while the Son was dead?
How could God the Father and God the Son be divided on the cross?
How can you say God doesn’t suffer if Jesus is God and he suffered?
There’s no such thing as a bad question, as teachers are supposed to say (and I mostly believe it). But there are complex questions, complex in the precise sense that their presuppositions are already so fully-loaded that the question can’t be answered until the presuppositions are made explicit, and, if necessary, rejected. These are the questions that bring out the pedant¹ in the professor, because they usually require some background.
The most interesting questions that arise as we contemplate the death and resurrection of Jesus are questions that require a couple of steps back. In particular, when somebody asks a hard question about what happened at the cross or the empty tomb, the question itself usually shows what they are presupposing about the incarnation itself. A mistake about the incarnation may go unnoticed at Christmas, only to play havoc with your understanding of Good Friday and Easter.
Here’s what I mean: When the Word became flesh, it was really the Word, and he continued to be the Word even in the flesh. If you are in the habit of thinking “become” means that something starts out in one state, but then undergoes a series of changes during which it ceases to be what it was and instead turns into the new thing that it wasn’t before but now is, you’ll have to give up that idea of becoming, in this case.
What would it even mean to say that God became human if by “became” we meant “stopped being God and turned into man instead?” When the impossibility of such a thing occurs to people, they sometimes want to solve the problem by referring to the Trinity: maybe, they say, only one third of God stopped being God and turned into man? But it doesn’t take much reflection to see what a disaster that is, and to admit that the Son of God is not one third of God. Other people punt to timelessness and try to account for God’s changy-not-changy shenanigans by saying it’s always what it is. This move is neither clear, effective, nor necessary. What’s really going on is that “became” doesn’t mean what we took it to mean. Fix that misunderstanding and there’s no need to let the confusion spread like gangrene.
When the Son of God became human, he did so not by ceasing to be divine and transforming into human. Instead, “without ceasing to be what he was, he became what he was not,” as Gregory Nazianzen said (Epistle 101). The Son of God took human nature into union with his own person; he assumed it and added it to himself.
We call this addition of human nature the hypostatic union, where “hypostatic” means personal and points out that this person, the eternal Son, having always had the divine nature, appropriated to himself a human nature all his own.