The Bible does not tell us when Jesus was born. The fact that shepherds were watching their flocks at night may hint that Jesus was born in February, when lambs also are born. This would be fitting, since Jesus is called the Lamb of God who takes away the sin of the world. But the shepherds’ nighttime watch could have happened any time of year, as the shepherds worked to keep their flocks safe from thieves and predators.
Christians celebrate the birthday of Jesus on December 25. Traditionally, that date is the first day of Christmas, a twelve-day season that continues until January 5. Often Christians complain that the world has stolen Christmas from the Church, turning a sacred holiday into a secular orgy of commercialism and worldly excess. Others say that the Church first stole Christmas from the world. In the northern hemisphere, celebrations of the winter solstice were common. Days had been getting shorter and nights longer all summer and autumn; after the solstice, days begin increasing in length. Winter weather continues for a few more weeks, but spring is coming. It’s a good time for a party, although in modern times any excuse will do.
Some Christians become defensive about the holiday and insist that the Church created this holiday apart from pagan or worldly suggestions. Complicated calculations are offered to demonstrate that the birthday of Jesus was known (or assumed) from the date of his death on the cross, a date known to be near the spring equinox because it happened at the time of the Passover. Supposedly, this calculation was done early in Church history and produced Christmas celebrations among even the first Christians. But I have read the writings of the Church Fathers, and I cannot find any discussion of the celebration of Christmas before the fourth century of the Christian (or Common) Era. Moreover, that discussion is based on a misunderstanding of a verse in the Bible, a misunderstanding that the earliest Christians probably would not have made.
A priest named Zechariah was burning incense in the Temple when he saw an angel. This angel promised Zechariah that his wife Elizabeth would bear a son, one who would be an important messenger in God’s plan. (That son is known as John the Baptist.) The birth of Elizabeth’s son was a miracle, because she and Zechariah were beyond the age when people generally become parents. This miracle repeats that of Isaac, who was born to Abraham and Sarah when Abraham was one hundred years old and Sarah was ninety.
Six months later the same angel visited a young woman, probably about fifteen years old, in Nazareth. The angel again announced a miraculous birth. This time the miracle would be conception of a son without the participation of a human father, because Mary was a virgin betrothed (promised or engaged) to a carpenter named Joseph. The angel specifically told Mary that Elizabeth, her relative, was six months into her pregnancy. Mary visited Elizabeth, then returned to Nazareth. John was born to Elizabeth, and six months later Jesus was born to Mary.
Because Zechariah was a priest performing priestly duties in the Temple, some Christians assumed that Zechariah was offering the annual sacrifice for the Day of Atonement in the Most Holy Place within the Temple. Luke does not mention the sacrifice of atonement; he says only that Zechariah was burning incense. Nor does Luke call Zechariah a high priest; he notes that Zechariah was taking his turn to burn incense in the Temple, along with other priests. But, misreading Luke’s account, those Christians deduced that the announcement of Elizabeth’s pregnancy and John’s coming birth must have been in September, at the time of the Day of Atonement. Therefore, the announcement to Mary six months later would have been in March, John would have been born in June, and Jesus would have been born in December. These two announcements and two births fall near the two equinoxes and two solstices, allowing for celebrations near these events among Christians (although the announcement to Mary, dated to March 25, is easily overshadowed by the greater celebration of Easter the same time of year).
Does it matter when Jesus was born? The earliest Christians didn’t seem to consider the date important. Christians celebrate, not just a birthday, but the miracle of the Incarnation, the fact that God became human to reconcile humans to God. That miracle merits celebration at any time, but why not observe it after the winter solstice, when the days are becoming measurably longer? As Jesus is the Light of the world, the Light the darkness can neither comprehend nor extinguish, so Christians celebrate their Savior at the same time that other people celebrate for other reasons. J.