There is much debate on why December 25th was chosen as the day Jesus was born.
There is little Biblical evidence that reveals the date of Jesus’ birth. Luke 2:8 refers to shepherds in the fields suggesting Jesus’ birth took place in the spring when shepherds were with their flocks during lambing.
Maybe not coincidentally, John refers to Jesus as the Lamb of God (John 1:29).
Clement of Alexandria (150 AD – 215 AD), an Egyptian Christian teacher, had cited May 20th and April 20th or 21st as possible dates of Christ’s birth fitting the spring theory.
By 400 AD, December 25th along with January 6th were considered the dates for Christ’s birth with December 25th the leading contender and eventual winner. The December date was listed as Jesus’ birth on an ancient Roman almanac from the 4th century that listed the death dates of early Christian martyrs.
The most popular reason why December 25th was chosen is because the church was Christianizing the pagan celebration of Sol Inviticus — a sun-god — that Roman Emperor Aurelian had introduced on that date in 274 AD
However, in his article, How December 25, became Christmas, historian Andrew McGowan suggests December 25th was selected for a much different reason.
He notes that it wasn’t until later — the 12th century — that Christian writers first suggested the date was chosen deliberately to overrule the sun-god festival.
McGowan says early Christian writers from the 4th century noted December 25th was the date of the sun-god holiday but considered Christ’s birth falling on the same day as coincidental.
Some even considered it providential that God would overrule this pagan holiday. This does not suggest any intentional attempt to end a pagan celebration.
If this is the case then how did they arrive at December 25th?
Because of the Biblical record, the early Christian writers had a much more exact estimate of the day Christ died. Tertullian (160 AD to 225 AD), a Christian apologist from Carthage, said March 25th was the date of Christ’s death.
An interesting theory began to develop shortly after this that Jesus’ conception and death took place on the same day of the year — March 25th. Basically, Jesus arrived from heaven (His conception) and went back to heaven (His death) on the same day.
In the culture of the day, if this happened, it indicated that a person was particularly blessed by God. Of course, it was natural to presume this is what happened to Jesus.
In fact, a special religious day was eventually developed to celebrate Gabriel’s announcement to Mary that she had conceived by the Holy Spirit (Luke 1:26-39). Called the Feast of the Annunciation or conception, it is still celebrated on March 25th in the Catholic Church particularly among those who revere Mary.
As this theory gained a foothold, others began to note if the Holy Spirit conceived Jesus on March 25th, then His birth would have been nine months later — towards the end of December.
McGowan says one of them was Christian theologian and philosopher Augustine (354 AD – 430 Ad). In his book, On the Trinity, Augustine, citing the March 25th conception date stated that Jesus was born December 25th as was traditionally accepted. — EZ
- How December 25th became Christmas: Bible History Daily