Why did God become human? Simple answer: To destroy death. Fr. Ted Bobosh writes:
God becomes human in order to die so that He cdan destroy death and enable humans to become divine and live in life everlasting. Only by becoming mortal can God defeat death — not prohibit it, or simply avoid it or banish it — but actually take it on and trample it down and triumph over it.
The Incarnation — God takes on not only human flesh to save it, but also takes on death to destroy it. For in the eternal kingdom of Heaven death is destroyed not simply defeated (Revelation 20:14, 21:4).
Read more about the deep mystery of the incarnation of the Word of God here: