The Date of Christmas

How do we know the year of Christ’s birth? What proof do we have that he was born on December 25th?
Turning to the scriptures for information about the timing of Christ's birth doesn't prove very helpful. The two gospel accounts of the nativity contradict each other. Matthew says that Jesus was born ‘in the days of King Herod’. King Herod died in the early months of what we would call 4 BC.
Luke's infancy narrative states that Jesus was born during the time that Quirinius was governor of Syria. That would make the year of Christ's birth 6 AD, 10 years later than that given in Matthew's version.
The traditional year of Jesus' birth was determined in the mid-sixth century by Dionysius Exiguus, a monk and scholar who set the calendar according to the system we now know as AD (anno domini, ‘in the year of the Lord’).
But why December 25? Early Church documents show that the birth of Christ has been celebrated in Rome on December 25th since the early fourth century. A Martyrology (a register of Christian martyrs) from around the year 354 lists December 25 as the feast of ‘The birth of Christ in Bethlehem in Judea’.
Preaching a sermon at Antioch on December 25 in 386, John Crysostom speaks of this being the tenth year since the feast has been celebrated in the East, although it ‘has been known from of old to the inhabitants of the West and has now been brought to us’.
There are several theories as to why the 25th December was chosen. The most common is the belief that Christians took over the date of the pagan feast of the Unconquered Sun which was proclaimed by the Emperor Aurelian in 274 AD. As the days stopped getting shorter and the hours of sunlight began to increase at the time of the winter solstice (December 25 in early calendars), people celebrated the sun's rebirth. Christians, who saw Christ as the true unconquered light of the world, celebrated his birth date on the same day.
Some scholars have challenged this theory, questioning whether a persecuted minority would have adopted the feastday of a pagan God so readily.
Other researchers suggest a different approach. Scripture gives the date of Christ's death as 14 Nisan, the fourteenth day of the spring moon. It was calculated that the equivalent date in the Roman calendar was March 25. The writings of Augustine and others show that early Christians followed a tradition that said that the lives of patriarchs spanned a whole number of years from conception to death. This resulted in their conviction that Christ was conceived on the same date that he died, March 25. In fact we celebrate the Annunciation on March 25. Adding exactly nine months (because Christ is the perfect human being) gives December 25 as the date of his birth.
This date link between Christmas and Easter reflects a theological link. If it had not been for Christ's passion, death and resurrection, we would not be celebrating Christmas at all. It is interesting to note that the Orthodox Church uses the word pascha to describe both Easter and Christmas. An authentic celebration of Christmas draws us to the wood of the manger but then directs us to look beyond it to the wood of the cross.

Elizabeth Harrington