Yom Kippur Katan

Today is one of a number of days on the Jewish calendar that is noted as “Yom Kippur Katan,” literally Little Day of Atonement. It is observed on the day before Rosh Chodesh (the new month)* except when Rosh Chodesh occurs on Saturday* or Sunday, when Yom Kippur Katan is observed earlier on the Thursday prior (as is the case today).

Yom Kippur Katan is interesting in that it is not mentioned in the Shulchan Aruch (Code of Jewish Law), but appears to have become a common practice among the 16th century kabbalists in Safed and the tradition spread from there. The basis for the observance of Yom Kippur Katan was the fact that in Temple times a sin offering was included in the Rosh Chodesh offerings, indicating that Rosh Chodesh is a particularly opportune time for repentance and atonement.

Atonement on the actual day of Yom Kippur is accomplished through fasting and prayer, but Rosh Chodesh is also considered a minor festival on which one may not fast. Therefore, Yom Kippur Katan is observed just before Rosh Chodesh.

In certain times and places, it was common for most of the community to fast (sunrise to nightfall) on Yom Kippur Katan. Today, fasting is less common, but the special penitential prayers are still often recited during the afternoon service in some synagogues.

* It is not observed the day before Rosh Hashana (the 1st of Tishrei); the day before Cheshvan, since Yom Kippur has just been observed; the day before Tevet, because it is still Chanukah; and the day before Iyar, since one does not fast during the month of Nisan.