Christmas is the moment when we recall the grace of salvation that we have already received, as Christ has left the heaven for us, the sinners.
Let this mind be in you, which was also in Christ Jesus: Who, being in the form of God, thought it not robbery to be equal with God. But made himself of no reputation, and took upon him the form of a servant, and was made in the likeness of men - Philippians 2:5-7