Social media is full of odd ideas about Christmas. Including claims that either we have no idea when Jesus was really born. Or that Jesus was really born in March. Or maybe September.
And that December 25 was picked to take over existing pagan holidays. In the mid-300’s, after Christianity was legalized by Constantine.
Why do we celebrate Christmas on December 25?
It all starts with today’s Gospel, when John the Baptist was conceived.
It begins with Zechariah, one of the priests of the Temple in Jerusalem. And John’s father. Zechariah is chosen to offer incense in the sanctuary of the Temple. The Holy of Holies.
The only time a priest would enter the Holy of Holies to do this would be at Yom Kippur, the Day of Atonement. According to the Hebrew (lunar) calendar, Yom Kippur occurs in late September/early October.
So what does that have to do with the birth of Jesus?
The Bible starts the Annunciation (when Jesus was conceived) by saying “in the 6th month.” On the Hebrew calendar, the New Year (Rosh Hashanah), is the 1st day of the month of Nisan. Which occurs in mid to late September. The 6th month of the Hebrew calendar (Elul) starts in mid to late March.
Why do we link the date of John’s conception with the date of Jesus’ conception?
Because at the Annunciation, the angel tells Mary that Elizabeth has been pregnant with John for 6 months. Since we know that John was conceived in mid to late September, this means that Jesus was conceived in mid to late March.
Traditionally, the Annunciation has been given the date of March 25th. The earliest written account of this tradition comes from the late 100’s (almost 200 years before Constantine and the legalization of Christianity).
Add 9 months to March 25th, and you get…