For many years people have repeated the claim that Christmas was placed on December 25 because Christians copied pagan festivals like Saturnalia or the feast of Sol Invictus. While these festivals did occur around the same time, the earliest Christian writings that refer to Christ’s birth do not mention paganism as the reason for choosing December 25. Instead, Christians in the second, third, and fourth centuries used biblical reasoning, symbolic chronology, and theological reflection to calculate the dates of Christ’s conception and birth. These internal Christian traditions give us a clearer window into how December 25 emerged.
This explanation centers on an early idea sometimes called the integral-age tradition and on the March 25 date long associated with the Passion and later with the Annunciation. While this reasoning appears most clearly in writers of the third and fourth centuries, it helps to show that the Christmas date came from inside Christian theological thinking—not as a reaction to Roman festivals.
Early Christian Interest in Dating Christ’s Life
Christians in the second century were already attempting to calculate the important moments in Jesus’ life. This is clear from Clement of Alexandria (around AD 195), who records several Christian efforts to determine the exact date of Jesus’ birth and His Passion.
In Stromata 1.21, Clement reports that:
-
Some Christians proposed dates in April or May for Jesus’ birth.
-
Others attempted to calculate the exact year and day of the Passion.
Clement does not provide a December 25 birth date, nor does he offer a symbolic framework connecting conception and crucifixion. What he does show is that Christians were actively calculating, not ignoring or dismissing such dates. This undermines the modern claim that “no one in early Christianity cared about the date.”
ATTENTION! I want to alert you to my Free booklet of 15+ Christmas myths! Check it out and tell me what you think. Grab yours by clicking the below link and I’ll also send you the latest iApologia updates!
15+ Myths of Christmas the Bible Doesn’t Teach
Explicit Evidence for December 25 in the Early Church
The earliest clear statement that Jesus was born on December 25 comes from Hippolytus of Rome, writing around AD 202. In his Commentary on Daniel 4.23.3, Hippolytus says:
“The first advent of our Lord in the flesh, when he was born in Bethlehem, was eight days before the kalends of January.”
“Eight days before the kalends of January” is December 25.
This testimony predates the Sol Invictus festival by roughly seventy years, meaning the Christian date was already circulating before the earliest evidence for a December 25 imperial Sol Invictus celebration.
The Integral-Age Tradition and the March 25 Connection
While Hippolytus gives December 25 as the birth date, he does not explain how he arrived at it. The earliest clear explanation of the method behind such dates comes from Christian writers like Tertullian and later Augustine.
Step 1: Dating the Passion to March 25
Tertullian (AD 197–220), in several works, places the Passion around March 25 based on Jewish calendar calculations. He gives the date of the crucifixion in terms of the Passover, which Christian chronologists often translated into 25 March in the Roman calendar.
Step 2: Matching Conception to Crucifixion
By the late fourth century, Augustine gives us the clearest articulation of the integral-age tradition. In On the Trinity 4.5, he states:
“He is believed to have been conceived on the twenty fifth of March, on which day also he suffered.”
Here we see the logic:
-
Jesus’ conception occurred on the same calendar date as His death.
-
This was viewed symbolically appropriate for the one whose life formed a perfect unity.
Step 3: Adding nine months
Once conception was placed on March 25, Jesus’ birth naturally falls nine months later, on December 25.
This is the earliest fully explained Christian logic for December 25. It is symbolic, theological, and based on Christian chronology—not pagan borrowing.
Further Evidence from Late Fourth-Century Christian Texts
The Apostolic Constitutions (around AD 380) give one of the earliest liturgical calendars and state:
“Keep the feast of the Nativity on the twenty fifth day of the ninth month.”
In the Syrian calendar, this corresponds to December 25. This shows that by the fourth century, December 25 was not only known but already part of established worship.
It is important that this text, like others, provides no reference to pagan festivals as motivation.
Contrast with the Pagan-Origin Narrative
No Christian writer before the medieval period ever says that the Church adopted December 25 in order to Christianize Saturnalia or Sol Invictus. Not one. The pagan-origin view arises much later, from post-Reformation speculation and 18th–19th century scholarship, not from ancient sources.
Instead, what we do find is:
-
Christians calculating the date of the Passion
-
A belief in a symbolic coherence between conception and crucifixion
-
A tradition that placed the conception on March 25
-
December 25 emerging as a natural result of that calculation
This does not prove December 25 is historically correct as Jesus’ literal birthday, but it does show that the date came from Christian internal logic, not from copying pagans.
Conclusion
The early Christian tradition that led to celebrating Christmas on December 25 was rooted in theological symbolism and biblical chronology. Writers like Hippolytus, Tertullian, and Augustine show that Christians were deeply engaged in understanding the timing of Christ’s life long before any supposed need to compete with Roman festivals.
By grounding conception in March 25 (the same date as the Passion) and counting nine months forward, Christians arrived at December 25 as a meaningful and theologically coherent date. This tradition offers a clearer window into early Christian thought and demonstrates that the December 25 celebration stands firmly within Christian historical reasoning rather than pagan imitation.
I would love for you to come along with me and not miss a post! In the future, I plan on giving more resources and answers. Plus, I want to send you a Free Quick Guide why I think science points to God. I would love for you to have this Free Quick Guide and the latest posts straight to your inbox. Please grab your Free Quick Guide why I think science points to God here.
So, what did you think? Feel free to share your thoughts below!
