The near universal celebration of the birth of Jesus Christ, or Christmas, on December 25th dates to the early 4th century.
Now, we have all heard the allegation: the date, December 25th, was settled on by the early Catholic Church to counter (or rather eclipse) the birthday celebration of the pagan “Invincible Sun” god, or Sol Invictus, held the same day.
Thus, many claim, not only is December 25th not at all the real birthday of Jesus, but even more, the date exposes how the early Church merely usurped pagan legends and myths in the covert fabrication of their own.
Well, upon further study it is clear that, not only is this allegation highly unconvincing, it is historically suspect.
One of the earliest presentations of December 25th as the birthday of Jesus Christ was given by St. Hippolytus of Rome in his commentary on the book of Daniel (specifically Daniel 4:23) given around the year 203 A.D.
The pagan celebration of the birthday of Sol Invictus on December 25th, however, was not instituted until latter that century, in the year 274 A.D., by Emperor Aurelian.
Thus, the earlier existence of the date within Christian circles as the real birthday of Jesus, makes a Christian borrowing from pagan sources rather unlikely. In fact, it is far more likely that the borrowing went the other way, that it was the pagan celebration of Sol Invictus that took December 25th from the Christians who already had it.
But this still leaves open the question; Why would Christians have chosen December 25th as the birthday of Jesus in the first place? Was their a reason for the date? Well, yes.
In his gospel, St. Luke tells of the births of both Jesus and John the Baptist. He tells us that the two births were separated by six months.
During the annunciation, when the angel Gabriel announces to the Virgin Mary that she would bear a son, Gabriel says, “Behold, your kinswoman Elizabeth in her old age has also conceived a son: and this is the sixth month with her who was called barren.” (Luke 1:36)
In addition, St. Luke tells us that John the Baptist was conceived after his father, Zachariah, saw a vision in the Temple and was struck dumb.
Zachariah was a priest of the division of Abijah and this vision occurred, Luke tells us, “when his division was on duty, according to the custom of the priesthood, and it fell to him by lot to enter the temple of the Lord and burn incense.” (Luke 1:8-9).
Now… ancient Christians believed that Zachariah was a ‘high priest.’ For example: the apocryphal “Infancy Gospel of James” probably written in the early second century, claims just as much.
So… if Zachariah was indeed a ‘high priest,’ as early Christians supposed, this implies that his offering of incense in the temple, and the accompanying vision announcing the conception of his son, occurred on the Jewish Day of Atonement (Yom Kippur).
The feast of Yom Kippur comes mostly in late September and most likely did so in the second century as well. Thus, early Christians simply did the math and calculated the dates of the two births.
If John the Baptist was conceived in late September, his birth would be nine months later in late June. If John the Baptist’s birth was in late June, the birth of Our Lord, whose conception was six months after John’s, would be six months after that in late December.
But this ball-park estimate of late December still leaves us questioning: Why did the early Christians settle specifically on December 25th?
To answer this question we must realize that, first, it seems that many early Christians thought, if even incorrectly, that Yom Kippur always fell on Sept. 24 – thus, John would have been born on June 24th-25th and Jesus six months later on December 24th-25th.
But second, given the measurements of the time, the ancients believed June 24th to be the longest day of the year. Likewise, they believed December 25th to be the shortest day of the year.
Given these astronomical events, settling on the dates June 24th and December 25th would have been quite natural.
St. Bede, in the 700’s, reflected on the meaning of these events and taught that, just as John the Baptist claimed, “this joy of mine is now full – He must increase, but I must decrease” (John 3:29c-30), so now does the very daylight do the same.
The daylight begins to decrease on the birthday of John, but begins to increase on the birthday of Jesus.
So, this is the real reason why the early Catholic Church began celebrating the birthday of Jesus on December 25th (and, for that matter, the birthday of John the Baptist on June 24th as she still does today).
Some will object that we have no absolute certainty that December 25th was the birthday of Jesus.
True… we do not have historical certainty… the objection is valid. But let us not assume that the early Church merely pirated the date from some pre-existing pagan holiday along with the accompanying symbols and folklore that came with it.
No, the early Catholics truly believed that Jesus was born on December 25th. Yes, we do not know for sure, but for us today it is a better date for the birthday of Jesus than any other.
-Fr. Brad Elliott, O.P.
Research provided by Fr. Augustine Thompson, O.P.
Be sure to check out our YouTube video ‘Why is Christmas in December?’ below: