Taanit

A ta'anit, or taanis (in Ashkenaz pronunciation), or taʿanith in Classical Hebrew is a fast in Judaism in which one abstains from all food and drink, including water. A Jewish fast may have one or more purposes, including:

The most well-known and well-observed fast is the fast of Yom Kippur, the Day of Atonement. This is the only fast day mentioned in the Torah (Leviticus 23:26-32).

Yom Kippur is a full fast, from sunset to darkness the following night. The other full fast is the Ninth of Av, Tisha B'Av. These fast days carry four additional restrictions - one may not wash his body, wear leather shoes, use colognes, oils or perfumes, or have sexual relations. Yom Kippur also has all the restrictions of Shabbat and Tisha B'Av has restrictions somewhat similar to a mourner sitting shiva.

All other fasts are minor fasts, observed from dawn to nightfall, without additional restrictions.

The fast of the Ninth of Av is one of four fasts that exist, in all or in part, in commemoration of events having to do with the destruction of the Temple. The other three are:

The fourth minor fast, observed on the day preceding Purim, is the Fast of Esther, Ta'anit Esther, in commemoration of Esther and the Jewish community of Shushan having fasted before she approached the king unbidden.

Additionally, Jewish custom requires firstborn males to observe the day preceding Passover as the Fast of the Firstborn, Ta'anit Bechorot. In modern times, however, this fast is rarely observed, as most firstborns opt to attend a siyum (festive meal celebrating the completion of a Tractate of the Talmud) instead. This is considered a legitimate form of "breaking" the fast, and therefore the firstborn may eat during the rest of the day.

Other customary Jewish fasts include:

Yom Kippur Katan (literally, the little Yom Kippur) - which is held on the 29th of Heshvan, Tevet, Shevat, Adar, (Adar Sheni in a leap year), Iyar, Sivan, Tammuz and Av. Special selichot are recited during the mincha service on those days. If the 29th of those months falls on a Friday or a Sabbath, it is observed on the Thursday prior.

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