When was Jesus born? On Christmas day? We actually have very little clue as to what day Jesus was actually born. Though scientists and theologians have tried to pinpoint it, there is no way of knowing even whether or not he was born in December! We do know, however, why we celebrate Jesus on the 25th. Gnostic Christians in Egypt first celebrated Christ’s birth around 200 A.D.. Many church leaders identified January 6th as the day of Christ’s birth and thus celebrated Christmas then; today, we celebrate Epiphany (or the arrival of the Magi) on that day. In the early Roman church, pagan holidays were often “Christianized” to help convert people to Christianity. Several pagan holidays were celebrated on and around December 25th, include a day to worship the sun because of the solstice. In 336, a church leader declared that December 25 would be the day to celebrate the birth of Christ, and we still celebrate it on that day!
Historical Clues from Scripture
The gospel accounts of Christ’s birth do not provide us with a precise date, but they do offer historical details from which Christians have drawn different conclusions. Consider first the shepherds keeping their flocks by night. This seemingly minor detail is significant because, according to some historians, shepherds in Judea typically worked outdoors between the months of March and November. This nine-month range is rather broad, ironically excluding the winter month of December, but it has led some historians to doubt that December is a viable date for Christ’s birth.
On the other hand, some scholars contend that the historical evidence for this shepherding calendar is insufficient. For instance, a mild winter would have enabled the sheep to remain outdoors. Furthermore, the sheep grazed in the wilderness during the warmer months, but Luke indicates that the shepherds were not in the wilderness at that time. They were instead stationed just outside Bethlehem, thereby indicating that it may have been wintertime after all.
As a final historical detail, the Jewish Mishnah indicates that “the sheep around Bethlehem were outside all year, and those that were worthy for the Passover offerings were in the fields thirty days before the feast—which would be as early as February—one of the coldest and rainiest months of the year.”
It is therefore possible that Jesus was born in the month of December, but it is also impossible to know with any certainty. As a result of this insufficient data, Christians would spend hundreds of years attempting to calculate the date, and they arrived at very different conclusions.
The earliest evidence of a Christmas celebration was around 200 A.D. in Alexandria, Egypt. Described by the Christian writer Clement of Alexandria (ca. 160- ca. 220), these Egyptian Christians were deeply Gnostic, influenced by the Platonic belief that the physical world is a pale reflection of the ideal. They ascribed to an ideology in which the material is considered inferior to the spiritual, and this belief system shaped their understanding of the Incarnation.
These Gnostic Christians concluded that Christ’s birth was not physical in the traditional, human sense, but was rather a “manifestation” or epiphany of God’s Son on earth. There was, however, disagreement about the true moment of the epiphany. Some believed it was signified by Christ’s birth, while others pinpointed the divine manifestation at the arrival of the magi, or at Jesus’ baptism, or during his first miracle at the wedding at Cana.
Although this group of Christians celebrated Christmas in a manner much different from later generations, this practice marked one of the earliest observances of Christ’s birth and it shaped the development of the tradition.
Throughout the history of the Church, Christians have observed Christmas on numerous dates, including November 18, March 28, April 19 or 20, and May 20. However the most popular date prior to the establishment of December 25th was January 6th, and for several reasons.
Clement of Alexandria
The first major reference to January 6th as the day of Christ’s birth comes from Clement of Alexandria. Although he mentioned numerous groups who observed Christ’s birth on several different dates, he himself attempted to calculate the date of Jesus’ birth by analyzing the time lapse between Jesus’ birth and the death of emperor Commodus in 192. Using an Egyptian calendar, he determined the date to be January 6 (Stromata 1.21.145).
However, Clement was not alone in associating January 6th with Christ’s birth. In his extensive account of the Christian faith, titled Stromateis, Clement described the Egyptian Basilideans who used the Alexandrian calendar to calculate a date of January 6 or 10.
As Clement explained, these Egyptian Gnostics celebrated Jesus’ baptism on the eleventh day of the month of Tubi, which is the equivalent of our modern January 6th. This day was eventually adopted by other Christians throughout the Eastern Mediterranean regions.
An Adaptation of Pagan Culture
A final reason that Christians may have observed Christmas on January 6th was the surrounding pagan culture. One scholar explains:
“Christians often tried to replace a pagan feast with a Christian one to alleviate the difficulties of conversion. In Egypt January 6 had a dual significance as a festival of the virgin goddess Kore and the birthday of the deity Osiris. By the second century, some Christians claimed this date for themselves.”
January 6 and Epiphany
Although December 25th became the official Christmas feast day of the Western Roman church, January 6th remains the day that Christians celebrate Epiphany. As a faint echo of the Egyptian Gnostic tradition, our modern observance of Epiphany marks the visit of the magi. January 6th also remains the official Christmas day of the modern Armenian church.
Additionally, the period between December 25 and January 6 constitutes the 12 Days of Christmas.
As already described, the early church periodically Christianized pagan holidays in order to facilitate the integration of converts. This practice is believed by some scholars to have motivated the establishment of December 25 as the Christmas feast day, which coincided with the popular pagan celebration of the winter solstice, the shortest day of the year.
In order to understand the church’s decision to align its Christmas feast with the winter solstice, it is first important to clarify that the date of the winter solstice has changed over time. During the early church, the winter solstice occurred on December 25, whereas today it occurs on December 21 or 22.
During the first two centuries of the church, the surrounding Roman culture commonly associated the winter solstice with worship of the sun. This association was a logical one: “As the shortest day of the year, it signaled the continual growth of the sun which…became larger and more powerful day by day.”
In the year 274, Emperor Aurelian officially instituted “the cult of Sol Invictus, the Unconquered Sun.” He also declared that December 25, the winter solstice, was to be celebrated as the Sun god’s birthday. The day was known as the dies natalis Solis Invicti (the birthday of the undefeated sun). The date subsequently became a major feast day in the Roman Empire.
December 25 carried additional significance owing to a Persian religion devoted to the virility god, Mithra. Mithra, who attracted followers within the Roman military, was described as a son or companion of the sun. Mithra shared his birthday with the sun god, which happened to be December 25.
Amidst these neighboring traditions, the local church in Rome officially claimed December 25 as the dies natalis Christi or “the natal of Christ.” This particular proclamation, which occurred in 336, was accompanied by no explanation. It implied that the church had long been celebrating Christmas on December 25, and no further discussion was necessary.
Although there is little historical evidence explaining why this date was chosen, most scholars contend that it was no mere coincidence. Some historians surmise that Christians intentionally supplanted the pagan Sol Invictus with the Christian Sol Iustitiae (the “Sun of Righteousness).
One final motivation for choosing December 25 may have been the Saturnalian festival that took place from December 17 to 23 each year. This pagan celebration honored the god Saturnus, and it involved “the exchanging of gifts, drinking, playing games, and often lewd behavior.” Concerned that Christians might succumb to this debauchery, it is possible that the church was further motivated to secure December 25 as a counter to the pagan festival.
Although the pagan festivals have provided a popular explanation for the December 25 dating, there is little direct evidence of the connection. The evidence is largely circumstantial, which has led some scholars to raise a different possibility corresponding with Christianity’s Jewish roots.
In the year 200 A.D., Tertullian of Carthage reported that Christ died on March 25 of the Roman calendar. Influenced by ancient Jewish theological texts, some Christians may have believed that the date of Christ’s death was also the date of his conception. The shared date was a symbolic tying together of creation and a redemption. In such a case, Christ would have been conceived on March 25, which is exactly nine months prior to December 25.
There is ample evidence that this belief played a part in the tradition. In On the Trinity, Augustine wrote,
“For he [Jesus] is believed to have been conceived on the 25th of March, upon which day also he suffered; so the womb of the Virgin, in which he was conceived, where no one of mortals was begotten, corresponds to the new grave in which he was buried, wherein was never man laid, neither before him nor since. But he was born, according to tradition, upon December the 25th.”
To this day the Feast of Annunciation, which marks the day of Christ’s conception, is celebrated on March 25.
Not unlike the speculation about Christmas’ pagan roots, there is an element of educated speculation guiding this latter theory. The reality is that scholars are not altogether sure. As a result, the history and reasoning behind our December 25 Christmas festivities will remain forever shrouded in some degree of mystery.
 Kelly, Joseph. The Origins of Christmas. Liturgical Press, Collegeville, MN, 2004, p. 55
 Hoehner, Harold W., Chronological Aspects of the Life of Christ. Zondervan, 1978, p. 26
 Martindale, C.C. (1908). Christmas. In The Catholic Encyclopedia. New York: Robert Appleton Company. Retrieved September 5, 2011 from New Advent: http://www.newadvent.org/cathen/03724b.htm
 Kelly, 2004, p. 56
 Kelly, Joseph. The Feast of Christmas. Liturgical Press, Collegeville, MN, 2010, p. 15
 Talley, Thomas. The origins of the liturgical year. P. 119
 Kelly, 2004, p. 57
 Kelly, 2010, p. 15
 McGowan, Andrew. “How December 25 Became Christmas.” Biblical Archaeology Review, http://www.bib-arch.org/e-features/christmas.asp
 Kelly, 2004, p. 62
 Ibid. p. 64
 Ibid. p. 63
 Ibid. p. 64
 Ibid. p. 66
 Ibid. 64