Q. I have a question, if God the Son's nature is true God and true man, then what was His nature during creation?
A. Ummm... Let's clarify a few ideas. Might get a bit technical, but I'm sure you can follow...
God is three persons in one nature; three who's in one what. We know this because Jesus spoke of the Father as God, He spoke of Himself as God and He spoke of a third person - the Paraclete or Consoler or Holy Spirit, as God. Nevertheless, He spoke of them as one. Just to give one example: "Go therefore and make disciples of all nations baptising them in the NAME of the Father and of the Son and of the Holy Spirit" (Mt 28:19). Note he says "in the name" not "in the names".
If you point at God and ask WHO is that? You can give three correct answers: God the Father, the Son or the Holy Spirit. If you point and ask WHAT is it? There's only one answer: God.
God the Son entered time and assumed a human body like we all have. From that point in time God the Son had one who and two what's. One who that we now refer to as Jesus Christ; two what's that are one divine and the other human. You point at Him and ask WHO is that? There's only one correct answer: He is Jesus Christ. If you point and ask WHAT is He? You can give two correct answers: He is God and He is man.
That newborn human baby whose birthday we are celebrating these days is the same God that created heaven and earth and all that is in them, created space and time and all that is in them, created you and I... He is perfect God equal to the Father and the Holy Spirit; He is also perfect man with a human body and human soul like you and I.
Hope you've wished Him a happy birthday!
30th December 2015