I didn't know that there is actually no proof that Jesus was born on Dec 25th on the year dot (sorry, I always wanted to say this). I quote:
The 12th century Syriac bishop, Jacob bar-Salibi, had this to say: It was a custom of the Pagans to celebrate on the same 25 December the birthday of the Sun, at which they kindled lights in token of festivity. In these solemnities and revelries the Christians also took part. Accordingly when the doctors of the Church perceived that the Christians had a leaning to this festival, they took counsel and resolved that the true Nativity should be solemnised on that day.
Obviously, we don't really know the date of the birth of Jesus Christ. The gospels do not say and the early church didn't much care about his physical birth. Until the Church Fathers got around to settling such questions in the 4th century, there was a grab bag of guesses. According to St Clement of Alexandria (2nd C):There are those who have determined [the day] of our Lord’s birth; and they say that it took place in the 28th year of Emperor Augustus, and in the 25th day of [the Egyptian month] Pachon [May 20]... Further, others say that He was born on the 24th or 25th of Pharmuthi [April 20 or 21].
Clement dismissed such dates out of hand. Instead, his own calculations showed that Christ was born on November 17, in the year 3 BC. A century later, a God-inspired theologian announced that Christ, the new "sun of Righteousness", was born on March 28 since the Creation began with the spring equinox (= March 25] and the Sun was created on the fourth day. So that was that (or so he thought). Before long, however, another learned priest calculated that the birth date was April 2 in the year 8 AD -- 5500 years to the day after the Creation, as he had worked it out himself. And then, of course, there were many who celebrated 8 January (Epiphany), still Christmas day in many Orthodox churches.
But no one had yet suggested December 25th.
It is only with the famous Calendar of Philocalus (a list of the early bishops of Rome and Roman festivals) written in 354 AD that we find, given for the year 336, December 25: natus Christus in Betleem Judeae, "Christ was born in Bethlehem of Judea".
But worry not, its the date of the birthday of the Sun. Since I am also named after the Sun God, I will celebrate my birthday on Dec 25 with a tree, exchange presents, sing songs, eat like a pig and wear silly hats, and pop crackers.
Merry Christmas everybody, have a wonderful time.