Since at least the fourth century in Rome, Christians have celebrated the incarnation and nativity of Jesus Christ on December 25. There is more than one theory about the origin of this festival day. Some have suggested that it was established to replace the Roman feast of Natalis Solis Invicti (the “birthday of the unconquered sun”). Others believe that Jesus was conceived on March 25 (coinciding with the date of his crucifixion, as recorded by some witnesses in the early church); December 25 is exactly nine months later.
Regardless, the time between December 25 and January 6 (Epiphany) has become an occasion for the church to celebrate and give thanks for the arrival of God’s Word made flesh — the light of God that has come into the world, the light that even death could not extinguish.