e celebrate our Lord’s Nativity on December 25th not so much because we’re certain that it’s the calendar date of His holy birth, but because it's just about the most fitting day for us to celebrate. The Holy Bible doesn’t give us the precise date, and in fact we didn’t start to celebrate Christmas in the Latin West until the middle of the 4th century.
But it’s very fitting that we do celebrate it on that date! There is an ancient tradition that the Annunciation, when the Archangel Gabriel told our Lady of our Lord’s Incarnation in her immaculate womb, happened on March 25th – the same day that the ancients thought the world began, and the day the ancients understood our Lord to have died on the Cross. So we have the creation of the world, the Annunciation (and eventually the Crucifixion) … and so precisely 9 months later, Christmas on December 25th!
Or how about this for another ancient Christian explanation of the date of our joyful feast: December 25th is shortly after the Winter Solstice, the shortest day of the year, the day with the least amount of light (at least up here in the Northern hemisphere!), and so it’s most fitting that the Light of the World, Jesus our Savior, should come into the world and begin to fill the world with His radiant light.
"… it's most fitting that the Light of the World, Jesus our Savior, should come into the world and begin to fill the world with His radiant light."
Christmas is on December 25th not because we’re absolutely certain that He was born on that date, but rather because it’s just about the most fitting day for us to celebrate His birth.