Frank W. Nelte

July 1996

The Names of the Months in the Jewish Calendar

When Ezra returned to Jerusalem from the Babylonian captivity in 457 B.C., he instituted the Babylonian calendar, which was also used by the Medo-Persians, for use amongst the Jews. He simply adapted the names of the months for use by the Jews.

Here are the names of the months in the Babylonian calendar, and the corresponding names in the Jewish calendar.

 MONTH # BABYLONIAN NAMEHEBREW NAME 
 1 Nisanu Nisan
 2 Aiaru Iyyar
 3 Simanu Sivan
 4 Duzu Tammuz
 5 Abu Ab
 6 Ululu Elul
 7 Tashritu Tishri
 8 Arahsamnu Heshvan
 9 Kislimu Kislev
 10 Tebetu Tebeth
 11 Shabatu Shebat
 12 Addaru Adar
 (13 Addaru II Adar II)

The point is that the calendar in use in Babylon was the same type as the Jewish calendar, based on the months starting with the new moons. And in the Babylonian calendar the year also started with "Nisanu" in the spring. It seems like Ezra had no problem accepting all those Babylonian names and VOLUNTARILY used them. The Babylonian calendar was the same type of calendar, governed by exactly the same principles, and therefore Ezra was agreeable to readily using the same names for the months, as were used by the Babylonians. That clearly makes it looks like a copy of the Babylonian calendar.

THE JEWISH ENCYCLOPEDIA, article "Calendar, History of" states:

"The Babylonian years were soli-lunar; that is to say, the year of 12 months containing 354 days was bound to the solar year of 365 days by intercalating, as occasion required, a thirteenth month. Out of every 11 years there were 7 with 12 months and 4 with 13 months." (Volume 3, page 499)

[COMMENT: This statement refers to the time before Meton discovered the 19-year cycles in the 450's B.C.. At some point after Meton's discovery they also implemented the 19-year cycle. However, it shows that the Jews themselves were, prior to Meton's discovery, also not yet aware of "19-year cycles".]

The article continues to state:

"The Talmud (Yerushalmi, Rosh ha-Shanah i.1) correctly states that the Jews got the names of the months at the time of the Babylonian exile." (page 499)

So when the Jews returned from the Babylonian captivity, they brought the Babylonian calendar with them. They rejected the old Hebrew names, and instead called their months by the Babylonian names.

It is clear that the present Jewish names for the months are simply linguistic adaptations of the Babylonian names. This shows that the Jews in Ezra's time and thereafter used the same calendar as the nations around them, with the same names for the months. The calendar the Jews used from that time onwards was not different from the calendar used by all the nations around them. They all used the same calendar, even as today the nations in Europe all use the same calendar, in which they have adapted the names of the months to their own particular languages. The slight differences today in the names of the months in Italian and English and Spanish and German, etc. do not detract from the fact that these nations all use the same calendar.

For the present Jewish calendar a number of its features can be led back to Babylon.

Frank W. Nelte