Not only is there a problem determining where Jesus was born—pinpointing when he was born presents a challenge, too. Despite all the festivities celebrating New Year’s 2000 as the 2,000th year since Jesus’ birth, most scholars are certain that he was not born in that hazy period between 1 B.C. and 1 A.D. (remember, there is no year 0). In fact, he was probably born several years before then—a seeming paradox if ever there was one! But remember that “Before Christ” was a term established several centuries after Jesus.
The current dating system, which places January 1, 1 A.D., a week after Jesus’ birth, was established in about 525 A.D. by Dionysius Exiguus (Dennis the Little), a Scythian monk, who hoped to repair a division in the church over the dates of Easter by preparing a new calendar. Rather than use the then-standard Diocletian system (counting the years since the reign of this late-third-century emperor, who had persecuted the Christians), Dionysius decided to count from Jesus’ birth. To do this, he used an earlier calendric system, which dated to many centuries before Jesus’ time—a Roman system based on the establishment of Rome. He fixed Jesus’ birth date as December 25, 753 A.U.C. (Ab Urbe Condita, from the founding of the city of Rome). It is not known how Dionysius chose that date. One theory is that he based it on the Book of Luke, which states that “Jesus was about thirty years old when he began his work” (Luke 3:23) and that this occurred “in the fifteenth year of the reign of Emperor Tiberius” (Luke 3:1). Tiberius’s reign began around 767 A.U.C., or 14 A.D., so 754 A.U.C. became 1 A.D. Dionysius’s system of counting years gradually caught on: Charlemagne made it nearly universal in the ninth century, and the calendar we use today maintains Dionysius’s calculations, with a few adjustments made by Pope Gregory in 1582. (Why December 25th was accepted as Jesus’ birthday is even more obscure; it may be related to the Roman festival of Saturnalia, which was celebrated on that date. It may also be related to the Jewish tradition of performing circumcisions one week after a birth—in Jesus’ case, on January 1.)
But Dionysius had miscalculated. As Matthew’s Gospel tells us, Jesus was born during the reign of Herod the Great. Herod died in 4 B.C., as is known from outside sources, such as Josephus, and from the dates of contemporaneous Roman leaders. This means that Jesus must have been born before 4 B.C. Various calculations, based on astronomy, history and the Bible, have come up with dates between 7 and 4 B.C.—which means that we are already a few years into the second millennium! But that won’t change anyone’s plans, or their calendars. The year 2000 it is, and 2000 it shall remain.