I’m reading Ed Feser’s book “Five Proofs for the Existence of God”. He starts with the “Aristotelian Proof” of a first cause with which we are all familiar, and draws the conclusion that ultimately God must be pure actuality; an unactualized actualizer.

Stated in my ineloquent way then - If someone (God) is purely actual, there exist no potential for change within him. Is this correct?

So here’s what I can’t figure out:

1) God became man in Jesus
2) Because God became man in Jesus he must have had the potential to do so.

Now I get that in the hypostatic union God didn’t actually change. Christ has two natures of being fully divine and fully human. Therefore, the divine didn’t acutually change but was joined with the human. However, God must have had the potential to be joined with a human nature.

Therefore, God couldn’t be pure actuality because He had any potentiality (to be joined to man in the hypostatic union).

I know I’m not thinking about this properly (because God is pure actuality), but I can’t figure out why. Can anyone help?

Thanks in advance!

Was my question that stupid?

God didn't have the potentiality to become man - and the Incarnation did not change anything in God. Human nature has a[n obediential] potency to be united to a divine Person. The relation between the two natures of Christ is real in the human nature but merely logical in the divine nature.

I needto be more clear - I didn’t mean say or even imply that God had potentiality to become man. However, I thought that I clearly said that the incarnation didn’t change God.

What I also said is that God must have had the potentiality to be joined with man in the hypostatic union. However, since God is pure actuality with no potentiality, I must be missing something.

I’m not sure your response addresses my question about God and the hypostatic union....at least perhaps I’m too think to understand what you meant. Could you rephrase or explain a little more?

Thanks!

I did address your concern. The relation between the two natures of Christ is real in human nature (there's a real potency in human nature to be joined to a divine Person which is actualized in Christ's human nature), but merely logical in God. This is because, as you said, God is pure actuality. There is no potency whatsoever in God (though there is power).

Also, if you state that God is not Pure Act, then you have no grounds for saying there is no change in God. If God has any potency whatsoever, then He can change. After all, potency is just a capacity for change.

Thanks. This ^^^ I’m starting to get.

What I didn’t understand is how God could have, what seemed to me, potentiality for the hypostatic union (since God is pure actuality and therefore, no potentiality exists). However, you have provided an explanation - that the relation is “logical in the divine nature”. But I’m not sure exactly what that means.

As I understand it, Christ is both fully divine and fully human. So is that true only from the human perspective?

Well you wouldn't say that God, in and of Himself, considering His divine essence, has a human nature, would you? But you certainly would say that Jesus, the man, in and of Himself, has both a human and a divine nature.

Yes, Jesus has both human and divine nature.

Jesus is God. Jesus became man. Therefore, His Divine nature was unified to the human nature. So that means God had the potential to have his divine nature unified to a human nature else it wouldn’t have happened.

However, God has no potentiality, therefore my reasoning is flawed. While everyone is trying to explain why my reasoning is flawed (which BTW, I fully accept but cannot identify why), I don’t completely understand the explanation.

So I appreciate the help, but its just not clicking for me.....

Then I invite you to revisit and reconsider TC's comments on the difference in logical and real relations. It is important--extremely important--to recognize that whereas we stand in real relations to God, that He stands in only logical relations to us. It's not an intuitive concept, but to claim that God is in real relations to us is to reduce Him to a being and thereby deny His simplicity and ultimately His very deity. Aquinas addresses to issue of real vs logical relations in ST Ia.3.6 and 13.7. I also address it a little here (pp 111-16 according to pagination; 113-18 absolutely).

OK thanks.

I knew this wasn’t going to be easy.

Think of it this way - God made the world, yet he didn't have a "potency" to create. Similarly he didn't have the "potency" to do miracles or to do reveal himself or to adopt you (in baptism). If God does not change, we can say that he lacks potency.

I got to tell ya, this is one I'm having a hard time getting my arms around....