Counting the Years How the Jewish year is numbered. The Jewish
calendar not only has its own unique months, but it also numbers
years differently from the secular calendar. The year 2003, for
instance, was roughly equivalent to the Jewish year 5763.
(Specifically, Rosh Hashanah, the Jewish New Year, in September
2003 marked the transition from 5763 to 5764). The counting of
Jewish years, as we know it today, dates from the Middle Ages.
In secular texts, Jewish time is often noted as “A.M.”--anno
mundo--literally, “years of the world.” (Occasionally, “A.M.” is
explained as standing for aera mundi, “era of the world.”) This
system of Jewish time is called the “Mundane Era” (English for
aera mundi) because those who invented it believed they were
calculating dates from the birth of the world. Chronologies of
the Bible and Temple The basis of the Jewish annual calendar is
ancient. The Torah speaks of the annual cycle of holy days and
festivals, and it was systematized by the sages well before the
fall of the Seco