Why was Jesus born as a baby?

"Jesus the Great High Priest - Therefore, since we have a great high priest who has ascended into heaven,[a] Jesus the Son of God, let us hold firmly to the faith we profess. For we do not have a high priest who is unable to empathize with our weaknesses, but we have one who has been tempted in every way, just as we are—yet he did not sin. Let us then approach God’s throne of grace with confidence, so that we may receive mercy and find grace to help us in our time of need." Hebrews 4:14-16 (NIV)