God Incarnate

I'm rereading the book, "A Severe Mercy" for the second time and came across an analogy that Sheldon Vanauken gave regarding how Jesus was fully human and fully God at the same time. It is a diaolgue that he and Davy had with a friend of theirs while in Oxford.

"Look, Richard," I said. "This afternoon Davy and I were talking about writing a novel of Oxford with the Studio in it, and us, and everybody. Now, assuming we could do it-"
"Assuming you could do it" said Richard, "I'd buy a copy. Not more than five shillings, though!"
"Listen" I said. "we're talking about the Incarnation. Okay, suppose I write it-its to complicated with two authors-and I put myself in it. There I am, walking down the High, wearing a Jesus tie-in the book. And let's say Imake up a lot of characters, in it, and I, the character, say whatever I would say in the various situations that occur in my plot."
"What abut the Incarnation?" said Richard.
"That's what I'm telling you, stupid fellow," I said with a grin.
"Don't you see? I am the incarnate in my book. I am out here writing it, so I'm like God the Father. But it's really me in the book, too, isn't it? So that's Jesus, the Son, right? The me in the book speaks my words - and yet they are speeches that I've probably never made in real life, not being in those situations. And yet can't you see that it's really me?"
"Um," said Richard. "Yes, right. I see. Go on."
"Well," I said. "All right. I'm out here, being the 'Author of all things' and I'm in the book, taking part in scenes of 'drammer' incarnate in my book. Now, the me in the book: he's all me, isn't he? And he's all character, too isn't he? Like the doctrine: all God and All man. It makes sense doesn't it? And one more thing, suppose the characters run away with the story - authors are always saying that that happens. It might be necessary, whatever I had originally intended, for me to get killed - um, crucified.......anyhow - you see?"
"You win," said Richard. "It does make sense that way. I'll have to thinkg aobut it."
"There something else, though," said Davy. "The other characters- made-up ones. Invented ones. If Van invents characters, they'll all, even the bad ones, have something of Van in them, won't they? So, you see? wea ll have something of God in us - God's spirit - but only the One, Jesus, is God Incarnate."