He did not just appear like a human; he became one. But by the word became, Christians do not envision a change to God’s nature. God never changed during any of the theophanies in the Torah, and he was not changing during his incarnation. Christians traditionally teach that God, rather than changing, was taking a human nature in addition to his divine nature. This doctrine is called the hypostatic union. When the Bible says that Jesus “grew in wisdom and in stature” or that Jesus died by crucifixion, Christians believe it is speaking with respect to his human nature, not his divine nature.
