Merry Christmas! The physician’s take in question is Luke, who authored both his gospel account and Acts for Theophilus, together comprising the largest part of the New Testament written by one author. He likely was not Jewish, though he might have been a Hellenistic Jew. And he was known as “Luke the beloved physician” (Colossians 4:14), not the faith-challenged technocrat. He would provide faithful service to the apostle Paul, a man of profound faith. Note to us all: medicine is not junior varsity healing.

Luke’s gospel gives the most complete and careful detailing of the setting, annunciation, gestation and birth of Christ, as one would expect from a person of medicine. He states his aim was to write “an orderly account” such that Theophilus (and we) “…may know the certainty of those things in which you were instructed” (Luke 1:3-4, NKJV). Faith coupled with scholarship is quite something. It can be very handy having a doctor around.

When Gabriel informs Mary that as a virgin she would conceive and give birth to Jesus, she offers two standout responses. First, Mary posed the question, “How can this be, since I do not know a man?” (Luke 1:34, NKJV.) God rewards honest inquiry, and Mary was asking in order to understand rather than to mock like Zacharias did when told by an angel of the Lord his aged wife Elizabeth would birth John the Baptist. Gabriel explained more to Mary, who then in verse 38 offered her now informed consent, “Behold the maidservant of the Lord! Let it be to me according to your word” (Luke 1:38, NKJV). (This is the deathblow to the recent fatuous and flippant claim that God molested Mary.)

And Christ was born. But when? December 25? Critics are fond of saying that date is simply a Christian cultural appropriation of the pagan celebrations of Saturnalia or Sol Invictus. Either claim is quite doubtful. Yale’s Berkeley Divinity School Dean Andrew McGowan’s “How December 25 became Christmas” is informative. He writes, “But early Christian writers never hint at any recent calendrical engineering; they clearly don’t think the date was chosen by the church. Rather they see the coincidence as a providential sign, as natural proof that God had selected Jesus over the false pagan gods.” McGowan details how scholars acknowledge that the popular pagan-festival-appropriation theory of Christmas is beset with difficulties. At the top of the list, “the first mention of a date for Christmas (c. 200) and the earliest celebrations that we know about (c. 250–300) come in a period when Christians were not borrowing heavily from pagan traditions of such an obvious character.” McGowan explains that Tertullian of Carthage documented (circa 200 AD) that the 14th of the Hebrew month of Nisan—when Jesus was crucified per the Gospel of John—lined up with March 25 of the Roman calendar. McGowan adds, “Jesus was believed to have been conceived and crucified on the same day of the year. Exactly nine months later, Jesus was born, on December 25.” Eastern Orthodox Christians used the Greek calendar to view April 6 as the date of Jesus’ conception—and subsequent crucifixion—and therefore, coming nine months later, January 6 as Christ’s birth. The gap between the western December 25 and the eastern January 6 provides us the 12 days of Christmas. McGowan made no mention of how a gift of a partridge in a pear tree led to the one of 12 lords a leaping. Scholarship is never finished.

A series of blog posts (1, 2 and 3) by apologist Lenny Esposito sheds more light on the dating of Christmas and of Roman festivals. He explains that Yale’s T.C. Schmidt translated Hippolytus’ Commentary of Daniel (circa 200 AD) and found five of seven manuscripts listed December 25 as Jesus’ date of birth. His contemporary, Clement of Alexandria, put the incarnation at March 25, writing in Stromata. Reportedly both Hippolytus and Clement associated the conception and death of Jesus as being on the same day of the year. Esposito notes from Thomas Tulley’s The Origins of the Liturgical Year the “belief within the early church that the date of the death of Jesus would also reflect either his birth or his conception.”

What about Saturnalia? It became a feast of three days beginning around December 17, not the 25th, so the dates are incongruent. An early church trying to redeem the date from pagan practice would have picked December 17 rather than the 25th for Christmas.

What of Dies Natalis Solis Invictus (“Birthday of the Unconquerable Sun”)? Esposito quotes several scholars to demonstrate that Emperor Aurelius dedicated a new temple of Sol Invictus, that the Sun cult in question didn’t care much about winter solstice, and that the anniversary feast of the temple’s dedication wasn’t moved to December, let alone December 25, until about 80 years later (354AD).

No biblical account—not even Luke’s—puts a date or even a month on the birth of Jesus, but John’s Gospel gives us one for the crucifixion: Nisan 14. Why do we celebrate Christmas on December 25 (Roman calendar) or January 6 (Greek calendar)? Most likely because the early church believed that Jesus’ conception and crucifixion occurred on the same date of the year: Nisan 14. Adding nine months of gestation to it lands us at His birth. Merry Christmas!