The Bible never mentions the date of his birth, focussing more on the importance of his death. Although it does leave a few clues: we’re told that on the night the shepherds were “keeping watch over their flock by night” (Luke 2:8). This suggests that the date falls during the period of lambing when the flocks were kept in the fields, usually between spring and autumn. But certainly not mid-winter.
Perhaps it is significant as to when Jesus’ birthday was ‘decided’. The leaders of the Church chose the date of December 25th in the early fourth century, and the first Feast of the Nativity was held in Rome in 336AD. The Church at this time was one with the Roman state and Emperor. Constantine legalised Christianity in 313, making it the religion of the state in 324 after defeating Licinius. The Church became a political outfit backed by the Imperial patron. Before this time the date of Jesus Christ’s birth had never been of importance to the average Christian, who worshiped in secret in Church-houses.
Almost half a century before the legalisation of Christianity, Roman Emperor Aurelian inaugurated Dies Natalis Solis Invicti, “the birthday of the unconquered sun” in reverence of the sun god Sol. Naturally, the date of the celebration fell around the time of the winter solstice when the days were about to get longer again. Sol (and other solar deities, including the Persian god Mithras) celebrated birthdays on the 25th December.
This is hardly a coincidence; the Church leaders under Constantine thought long and hard about connecting Jesus’ birth with a well-established Pagan festival.
The reason appears quite simple. Christianity, already fast becoming the majority religion of the Roman Empire, could convert Pagans if their winter solstice festival became a celebration of Jesus’ birth instead. Christ was already being described as the light of the world by then anyway – it seemed a natural step. Of course, Christianity didn’t only adapt Dies Natalis Solis Invicti – Yule was a Pagan festival from Scandinavia in late December in honour of Thor, and this too was incorporated. Yule logs are still seen at Christmas time today.
It may seem ironic that Christmas is an amalgamation of Pagan festivals, though the evidence is strong. The Catholic Encyclopaedia of 1908 noted that the Sol Invictus festival has a “strong claim on the responsibility” for the date of Christ’s birth. Indeed, Jehovah’s Witness’s don’t celebrate Christmas at all for that reason.
But whatever its roots, Christmas is still a time for giving, for family, for love and peace. If anything, it only makes it more interesting to think that over 1700 years ago there were similar celebrations concerning the birth of Pagan sun gods.