Abstract

In Western tradition, the Nativity of Jesus is placed on December 25, 1 BC, according to the calculation made by Dionysius Exiguus in the sixth century. In Eastern tradition, January 6 is associated with both the birth of Jesus and the Epiphany (visit of the Magi). The historicity of events related to the Star of Bethlehem and the accuracy of tradition in determining the beginning of the Christian era have long been debated. This study, conducted through astronomy and the reconstruction of ancient calendars, has shed new light on this longstanding issue. In fact, an ancient fourth-century source, the Apostolic Constitutions, indicates that the Nativity of Jesus occurred on the 25th of Kislev, the first day of the Jewish festival of Hanukkah. The same source places the Epiphany of Magi on the 6th of Tevet. The astronomical-calendar analysis shows that, under certain assumptions, the 25th of Kislev and the 6th of Tevet can exactly coincide with the dates of the Eastern tradition for both the Nativity and the Epiphany, i. e. January 6, precisely at the beginning of the Christian era, according to the calculation made by Dionysius Exiguus. The probability that this is coincidental is so low that it implies these traditions must necessarily have a historical origin, demonstrating the reasonableness of the faith passed down to us by the early Christians.