Tomorrow begins a 12-day celebration, throughout the world, of the birth of Jesus Christ. December 25th is the “First Day of Christmas.” After the 12th Day of Christmas, on January 5th, we reach Epiphany (known as Theophany to our Eastern Orthodox neighbors).
While different Christian traditions have celebrated in different ways and have emphasized different days of this season, all Christians have marked December 25th as the birthday of Jesus going back at least to its first explicit mention in 354 A.D.
No serious scholar—Christian or otherwise—doubts that Jesus was born two millennia ago. But neither the Bible nor any other historical record names the season, month or day of his birth. Lacking such a record, scholars in recent centuries have challenged the December 25 date.
The most popular challenge arose from the “History of Religions School” which assumes that all religions are man-made. Looking for a man-made “reason for the season,” these scholars theorized that a festival for the pagan sun god, Sol Invictus, was co-opted by the Christian Church in a deliberate attempt to oppress pagan rivals.
They seized on the fact that Sol Invictus was associated with December 25. But they neglected to notice that Sol Invictus was not a Roman holiday until Emperor Aurelian invented it in 274. By then, the date of Christmas had already been calculated by Tertullian in 200 A.D. William J. Tighe wrote a very good synopsis of this history in Touchstone Magazine (December 2003) called, “Calculating Christmas.”
Tertullian’s calculations are not necessarily correct, but he shows two things. First, Christmas was not determined by the Sol Invictus. If anything, the Sol Invictus was determined by Christmas. Second, and more importantly, Christmas relates directly to the cross of Jesus. The date of Christmas is a by-product of Latin Christianity’s attempts to calculate the exact date of Jesus’ crucifixion.
Today, nearly the entire world uses the calendar of the Roman Empire based on the sun. But the Jews of the Bible marked time by the moon. As anybody knows, who pays attention to the cycle of the moon, these two calendars do not match up. Twelve “moonths” do not add up to 365 ¼ days. So, periodically, an extra month must be added to the lunar calendar in order to keep in sync with the sun.
The Old Testament Jews managed this by an occasional decree of the ruling Council. But when the Romans wiped out the Jewish nation in 70 A.D., nobody was left to make the needed adjustments. Later generations could only guess at what they would have done, but nobody in the Christian world had any contact with its actual doing.
That’s why Christian scholars had to make a series of calculations and guesses that can never be perfected. To make a long story short, Tertullian calculated that Jesus was crucified on March 25 in AD 29. We need not concern ourselves overly much about whether this date is correct. But what Tertullian and his contemporaries concluded next is most interesting.
Tertullian wrote, “Jesus died on the cross on March 25, the same day of the year as that on which He was conceived.” It would seem that he was not the only one who thought this. Even Hippolytus of Rome (+235) accepted this date. It seems that the entire Church, for 154 years before the first mention of Christmas celebrations, considered the day of Jesus’ crucifixion also to be the day of his conception in the womb of the Virgin Mary.
That is the basis for Christmas Day. Human birth regularly occurs nine months after conception. That would mean that Jesus’ birthday is on December 25. Again, nobody in the world has enough historical data to prove either that Jesus was born on December 25, or that He wasn’t. Regardless, the most important fact of Christmas Day is that Christians have tied the birth of Jesus to His crucifixion for more than 1,800 years.
Our Eastern Orthodox neighbors center their celebrations on January 6, the Theophany of Jesus, but they nevertheless acknowledge December 25 as His birthday. Western Christians tend to put the accent on December 25 and treat January 6, the Epiphany, as a lesser holiday. But both together—either knowingly, or unknowingly—anchor the season of Jesus’ birth in the purpose for that holy birth.
On the day that Jesus died, He stood before Pontius Pilate who asked, “Are You a king, then?” Jesus answered, “You say that I am a king. To this end I was born, and for this cause I came into the world” (John 19:37). As we sit down to Christmas dinners and attend Christmas services, this truth is shouted out by the very calendar itself.