On December 25, Christians around the world will gather to celebrate Jesus’ birth. Joyful carols, special liturgies, brightly wrapped gifts, festive foods—these all characterize the feast today, at least in the northern hemisphere. But just how did the Christmas festival originate? How did December 25 come to be associated with Jesus’ birthday?

The Bible offers few clues: Celebrations of Jesus’ Nativity are not mentioned in the Gospels or Acts; the date is not given, not even the time of year. The biblical reference to shepherds tending their flocks at night when they hear the news of Jesus’ birth (Luke 2:8) might suggest the spring lambing season; in the cold month of December, on the other hand, sheep might well have been corralled. Yet most scholars would urge caution about extracting such a precise but incidental detail from a narrative whose focus is theological rather than calendrical.

The extrabiblical evidence from the first and second century is equally spare: There is no mention of birth celebrations in the writings of early Christian writers such as Irenaeus (c. 130–200) or Tertullian (c. 160–225). Origen of Alexandria (c. 165–264) goes so far as to mock Roman celebrations of birth anniversaries, dismissing them as “pagan” practices—a strong indication that Jesus’ birth was not marked with similar festivities at that place and time. As far as we can tell, Christmas was not celebrated at all at this point.

This stands in sharp contrast to the very early traditions surrounding Jesus’ last days. Each of the Four Gospels provides detailed information about the time of Jesus’ death. According to John, Jesus is crucified just as the Passover lambs are being sacrificed. This would have occurred on the 14th of the Hebrew month of Nisan, just before the Jewish holiday began at sundown (considered the beginning of the 15th day because in the Hebrew calendar, days begin at sundown). In Matthew, Mark and Luke, however, the Last Supper is held after sundown, on the beginning of the 15th. Jesus is crucified the next morning—still, the 15th.

Easter, a much earlier development than Christmas, was simply the gradual Christian reinterpretation of Passover in terms of Jesus’ Passion. Its observance could even be implied in the New Testament (1 Corinthians 5:7–8: “Our paschal lamb, Christ, has been sacrificed. Therefore let us celebrate the festival…”); it was certainly a distinctively Christian feast by the mid-second century C.E., when the apocryphal text known as the Epistle to the Apostles has Jesus instruct his disciples to “make commemoration of [his] death, that is, the Passover.”

Jesus’ ministry, miracles, Passion and Resurrection were often of most interest to first- and early-second-century C.E. Christian writers. But over time, Jesus’ origins would become of increasing concern. We can begin to see this shift already in the New Testament. The earliest writings—Paul and Mark—make no mention of Jesus’ birth. The Gospels of Matthew and Luke provide well-known but quite different accounts of the event—although neither specifies a date. In the second century C.E., further details of Jesus’ birth and childhood are related in apocryphal writings such as the Infancy Gospel of Thomas and the Proto-Gospel of James. These texts provide everything from the names of Jesus’ grandparents to the details of his education—but not the date of his birth.

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