We celebrate the birth of Jesus on December 25, but it wasn’t really born then. No one knows the exact date of Jesus' birth, but the most likely date is the month of Tisri according to the Jewish calendar (August-September). According to some theories, he was born on December 20, but there are those who are born on April 18-19, respectively. this date is set for November 25, and other theories suggest that it was born at Epiphany, January 6th.