Oh, and Merry Christmas!

Many Mormons believe that they know the exact date Jesus was born - April 6. This date mostly comes from James E. Talmage's book, Jesus the Christ and from an interpretation from The Doctrine and Covenants 20:1. Other church leaders have referenced April 6 as being the date of Jesus' birth including Harold B. Lee, Spencer W. Kimball, and, most recently, Elder David A. Bednar. 

The Doctrine and Covenants is a part of the open scriptural canon of several denominations of the Latter Day Saint movement. Originally published in 1835 as Doctrine and Covenants of the Church of the Latter Day Saints: Carefully Selected from the Revelations of God, editions of the book continue to be printed mainly by The Church of Jesus Christ of Latter-day Saints and the Community of Christ, formerly known as the Reorganized Church of Jesus Christ of Latter Day Saints.

The passage in question is as follows:

1 The rise of the Church of Christ in these last days, being one thousand eight hundred and thirty years since the coming of our Lord and Savior Jesus Christ in the flesh, it being regularly organized and established agreeable to the laws of our country, by the will and commandments of God, in the fourth month, and on the sixth day of the month which is called April.