The Bible does not provide a date for the birth of Jesus. It is necessary to look at the information that is in Scripture and at the response by early Christians, AD 300 or earlier.
Early churches connected the incarnation and the death of Christ.
The Scriptures do not provide an exact date for the birth of Christ. However, they do inform us that the incarnation of Christ began with the announcement to Mary of the conception of Christ (Luke 1:35).
Early Christians honored the themes of Jesus’ incarnation, atonement and resurrection when they celebrated the Passion of Christ on April 6 which is the solar equivalent of 14 Nisan.
Christ’s death coincides with his conception. If you accept the date of April 6 for the conception and add 38 weeks for a typical human gestation period, then you will conclude with the plausibility of a birth date during the week of December 25. I am using our modern calendar for simplification.
The twelve days of Christmas fall between December 25 and January 6. There would be 40 weeks between the annunciation (conception) and Epiphany (revealiing) on January 6. Epiphany is the celebration of the revelation of Jesus as God incarnate. The Armenian Church celebrates January 6 as Christmas Day. (Although, Gaghant Baba brings gifts to children on New Year’s eve.)
More ancient references
About A.D. 200, Clement of Alexandria wrote that some theologians confused the phrase “ninth month” with the ninth month of their Egyptian calendar. Therefore, they mistakenly celebrated the birth of Jesus on 25 Pachon (20 May). Clement also writes that some Alexandrians placed Epiphany on 11 Tybi (January 6). In 418-427 A.D., the monk John Cassian writes that Egyptian monks still honored an ancient celebration on 6 January.
In A.D. 243, the date of December 25 was proposed for the celebration of the nativity in De pascha computus.[a]https://scaife-perseus-org.translate.goog/reader/urn:cts:latinLit:stoa0104p.stoa009.opp-lat1:1-5/?_x_tr_sl=la&_x_tr_tl=en&_x_tr_hl=en-US
In A.D. 311, the Donatist schism occurred. One point of contention regarded the date of December 25 for the nativity. This disagreement about that date documents the fact that such a date was well accepted by A.D. 300.
In a document entitled the Chronograph of 354, December 25 is listed as “VIII kal. Ian. natus Christus in Betleem Iudee.”[b]https://www.tertullian.org/fathers/chronography_of_354_06_calendar.htm
What about the Solstice Invictus?
Early Christians were aware that the birth of Jesus occurred near the winter solstice, a day with the least minutes of daylight. They did not borrow the Solstice as the date, they accepted the tradition of the conception coinciding with the Passion week. The death of Jesus is what places the date of His birth, not the other way round.
Early Christians rejected pagan practices. Many were martyred for their rejection of paganism. The actual recorded history denies any spiritual connection to sun worship or other pagan worship activities. It wasn’t until later that anti-Christian criticism brought slanderous accusations that Christians merely adopted existing paganism.
In A.D. 274, the Roman emperor Aurelian established December 25 as the date for the Natalis solis invicti, the Roman festival of the winter solstice. He chose this specific date to advance his own religious agenda: merging the newly-revived cult of Sol into the Christian monotheistic faith that was spreading throughout his empire, threatening to eclipse the old Roman religions.
The Christian significance of December 25 pre-dates the cultish Solstice Invictus.
Aurelian missed the solstice by four days, intentionally attempting to over-write the Christian date with a pagan festival. [c][based upon Thomas J. Talley, The Origins of the Liturgical Year, Liturgical Press; 2nd edition|January 1986]
Christians circulated a rebuttal in the form of a tract titled De solstitia et aequinoctia conceptionis et nativitatis domini nostri iesu christi et iohannis baptistae[d]“On the solstice and equinox of the conception and birth of Our Lord Jesus Christ and John the Baptist”. The Christian premise refused to accept the Roman god Sol because Jesus was a true God, a greater God.
“Therefore, our Lord was conceived on the eighth of the kalends of April in the month of March, which is the day of the passion of the Lord and of his conception. For on the day that he was conceived on the same he suffered.
…but our Lord, too, is born in the month of December . . . the eighth before the calends of January [25 December] . . . But they also call it the “Birthday of the invincible one” (Invictus). But who then is as invincible as our lord who defeated the death he suffered? Or if they say that this is the birthday of the sun, well He Himself is the Sun of Justice of whom the prophet Malachi said, “But for you who fear my name, the Sun of justice shall arise, and health is in his wings.”
What about the mention of the “sixth month” which places the conception in September?
Recently I visited the Church of the Annunciation. I asked my Israeli tour guide about the timeline that places Jesus’ birth in December. The tour guide objected to this timeline because of his knowledge of both the Christian Scriptures and the Hebrew calendar.
Luke 1:26,27 reads,
“Now in the sixth month the angel Gabriel was sent by God to a city of Galilee named Nazareth, to a virgin betrothed to a man whose name was Joseph, of the house of David.”
The sixth month of the Hebrew calendar is Elul, which places the annunciation in August and September. Nine months later would place the birth of Jesus in May and June.
However, my knowledgeable guide did not regard the context of “the sixth month”.
Luke 1:25,26 reads,
“Now after those days his wife Elizabeth conceived; and she hid herself five months, saying, ‘Thus the Lord has dealt with me, in the days when He looked on me, to take away my reproach among people.’ Now in the sixth month the angel Gabriel was sent by God to a city of Galilee named Nazareth, to a virgin betrothed to a man whose name was Joseph, of the house of David. The virgin’s name was Mary.”
The context does not indicate that the “sixth month” is a reference to the Hebrew calendar. It was the sixth of nine months of Elizabeth’s pregnancy. Six months had passed since Elizabeth’s miraculous conception.
Reading the entire Elizabeth and Mary passage confirms this pregnancy time sequence. Verse 36,
“Now indeed, Elizabeth your relative has also conceived a son in her old age; and this is now the sixth month for her who was called barren.”
“And Mary remained with her about three months, and returned to her house. Now Elizabeth’s full time came for her to be delivered, and she brought forth a son.”
What about the spring lambing season mentioned in Luke chapter 2:8?
And there were shepherds in the same region, living out of doors and keeping watch, guarding over their flock by night.
The Scripture does not tell us the quantity of wise men, nor does it tell us that Mary rode a donkey, nor does it directly mention an innkeeper. The angels did not “sing” to the shepherds. Jesus was not born in a “stable” in Bethlehem.
There is no “spring lambing season” recorded in Luke chapter two.
All these things have been added to the Christmas story when we re-tell it, maybe to make a children’s story more colorful for understanding.
Anyone who insists that it was spring lambing season does not do it on the basis of the text. The text merely says that the shepherds were out there but not what time of year. If it did, I would not have any basis for my minor controversy about December 25.
December in Bethlehem is normally somewhere around 50 degrees[e]F, so if necessary, well-prepared shepherds could plausibly be seated on the ground in December when the glory shone all around.
|↑c||[based upon Thomas J. Talley, The Origins of the Liturgical Year, Liturgical Press; 2nd edition|January 1986]|
|↑d||“On the solstice and equinox of the conception and birth of Our Lord Jesus Christ and John the Baptist”|