There is no shortage of internet blogs about Christmas being a “pagan” holiday that is tied to the winter solstice. Don’t worry: this is not one of them. It’s true that in 274 CE Emperor Aurelian established December 25 as the festival of Sol Invictus (unconquered sun); the decked out trees, presents, Santa Claus and jingle bells did not originate in the Gospels either. But the popularly-propagated theory that early Christians simply appropriated the solstice for celebrating the birth of their Savior may be fiction as well.
Even the third-century church leaders did not know on which day Yeshua was born. Historians trace the first mention of December 25th as Jesus’ birthday to a mid-fourth century Depositio Martyrum — a list of dates copied by Furius Dionisyus Philocalus, a friend of Pope Damascus. According to Augustine of Hippo, the Donatist heretics celebrated Christ’s birth on December 25th sometime in the fourth century as well. Yes, it took over 400 years for this exact date to surface among Christians, long after Aurelian and Constantine. Christian writers have speculated about Yeshua’s day of birth for centuries, but more importantly, they wanted to know the day of his conception — the true moment of the incarnation. But unlike pagans, Jews did not exactly celebrate birthdays in antiquity and there was no solid tradition to lean on for ascertaining Jesus’ birthdate.
The ancient rabbis believed that many great people were born and died in conjunction with the most important dates on the calendar. According to Rabbi Yehoshua, “In [the Jewish month of] Nisan the world was created; in Nisan the Patriarchs were born; in Nisan the Patriarchs died; on Passover Isaac was born; on Rosh HaShana Sarah, Rachel, and Hannah were remembered by God and conceived sons… in Nisan the Jewish people were redeemed from Egypt; and in Nisan in the future the Jewish people will be redeemed in the final redemption.” (b. Rosh Hashanah 10a).
In a similar fashion, Clement of Alexandria (third century CE) believed that since Jesus died around Passover, he was born around Passover. The theory is that, originally, the date of Jesus’ incarnation (conception) was the focus, not his birth. The further transformation of December 25th in the Christian tradition is another mystery.