“Dating the Birth of Christ,” by Jeffrey R. Chadwick, BYU Studies 49, no. 4.
The Church of Jesus Christ of Latter-day Saints has taken no official position on the exact date of Christ's birth. In his 1915 classic Jesus the Christ, Elder James E. Talmage maintained that Jesus Christ was born on April 6 in the year 1 BC. Talmage was apparently the first LDS writer to propose this particular date. Nearly a century has passed since his book appeared, and in that time it has become practically axiomatic among Latter-day Saints that Jesus was born on April 6 in that year. Two other Apostles, President J. Reuben Clark and Elder Bruce R. McConkie, published major studies on the life and ministry of Jesus Christ and proposed that Jesus was born in late 5 BC or early 4 BC. In this article, Jeffrey R. Chadwick, Jerusalem Center Professor of Archaeology and Near Eastern Studies, draws upon many sources—scriptural, historical, archeological, and astronomical—to shed light on the probable date of the Savior's birth. Using the known date of Herod the Great's death, information from the Book of Mormon about the length of Jesus's life, technical details about the Jewish lunar-solar calendar, the timing of the Annunciation to Mary, and other historical data, Chadwick narrows the window of time in which the Savior would have been born to December of 5 BC. The author is careful to deal with statements made by latter-day prophets supporting the April 6, 1 BC, date first proposed by Elder Talmage. Chadwick is able to show that these statements always occur in talks given about other topics (not expressly about the date of Christ's birth) and probably rely on Elder Talmage's assumptions. But a careful look at Doctrine and Covenants 20:1, upon which Talmage's proposal is based, shows that this verse was not a revelation by the Lord about his birth date. In fact, the verse is likely prefatory material dictated by Joseph Smith and recorded by his scribe with the express purpose of establishing the date of the Church's organization rather than the date of the Savior's birth.
How Christmas Came to Be on December 25 by Eric D. Huntsman, from his book Good Tidings of Great Joy, 6–7.
Because the Gospels do not give an exact date for Jesus’ birth, together with the fact that early Christians do not seem to have celebrated Christmas, later believers were left to guess at what seemed like a probable date. Perhaps the earliest suggestion was January 6, a date associated with both the visit of the Wise Men and Jesus’ later baptism. The idea that Jesus’ “new birth” at the beginning of his ministry (Mark 1:11, when God proclaimed Jesus to be his Son after he was baptized) replaced his birth as Mary’s baby (Luke 2:7) gave some credence to this date. January 6 was also initially popular with some Christians in Egypt, where the god Osiris, who was somewhat of a Christ-type in that he died and rose again, was also honored on January 6