Asara B'Tevetעֲשָׂרָה בְּטֵבֵת

Tenth of Tevet (Hebrew: עשרה בטבת, Asarah BeTevet), the tenth day of the Hebrew month of Tevet, is a minor fast day in Judaism. The fast commemorates the siege of Jerusalem by Nebuchadnezzar II of Babylonia. Like other minor fasts, Asara B’Tevet begins at dawn (first light) and ends at nightfall (full dark). Asara B'Tevet also belongs to a cluster of three early-Tevet losses that Jewish tradition mourns together: the completion of the Greek Septuagint translation of the Torah for King Ptolemy (Tevet 8), seen by the sages as a spiritual diminishment of the Torah; the death of Ezra the Scribe (Tevet 9); and the start of Nebuchadnezzar's siege (Tevet 10). The siege itself was the first link in a chain that, roughly two and a half years later, ended in the breaching of the city walls and the destruction of the First Temple. Like the other minor fasts, its purpose is less about deprivation than about reflection: the day is meant to awaken the heart to repentance by recalling how national catastrophe began. In modern Israel the Chief Rabbinate gave the day an additional layer of meaning, designating it Yom HaKaddish HaKlali, a general day to recite Kaddish and mourn for those whose date or place of death is unknown, including many victims of the Holocaust.

Asara B'Tevet falls on the 10th of the Hebrew month of Tevet, which on the Gregorian calendar lands in December or early January. The fast runs from dawn (alot hashachar, first light) to nightfall, when about three medium stars are visible. There is no Israel/Diaspora date difference. One timing feature is distinctive: Asara B'Tevet is the only minor fast in the fixed calendar that can fall on a Friday, and, unlike the other minor fasts, it is not postponed in that case but observed straight through to nightfall even after Shabbat has begun. It can never fall on Shabbat itself. When it does land on Friday, the unusual situation arises of a Torah and Haftarah reading at Mincha immediately before Shabbat.

The Torah reading is the standard fast-day portion known as "Vayechal" (after its opening word): Exodus 32:11-14 and 34:1-10, divided into three aliyot and read at both Shacharit (morning) and Mincha (afternoon). These verses recount Moses interceding after the Golden Calf and God revealing the Thirteen Attributes of Mercy, the same reading used on the other minor fasts (17 Tammuz, the Fast of Gedaliah, and the Fast of Esther). In the Ashkenazic rite a Haftarah, Isaiah 55:6-56:8 ("Dirshu Hashem b'himatz'o"), is added only at Mincha, not in the morning. There is no special mournful melody for Asara B'Tevet: the Vayechal portion is chanted in ordinary Torah trope and the Haftarah in ordinary Haftarah trope. The mournful Eicha (Lamentations) cantillation is reserved for Tisha B'Av and the Three Weeks and is not used here. (Sephardic, Yemenite, and other rites may differ on the Mincha Haftarah and aliyah divisions; the above follows predominant Ashkenazic custom.)

The core observance is refraining from food and drink from dawn to nightfall; on a minor fast, eating and drinking are the only prohibitions, so bathing, wearing leather, and other restrictions that apply on Tisha B'Av and Yom Kippur do not apply here. Selichot (penitential prayers) are added to the morning service, the long form of Avinu Malkeinu is recited at both Shacharit and Mincha, and the Aneinu prayer ("Answer us") is inserted into the Amidah by the prayer leader and by individuals who are fasting. The day is approached in a spirit of mourning, reflection, and repentance over the destruction of Jerusalem and the Temple. In Israel it is also widely observed as Yom HaKaddish HaKlali, with the recitation of a general Kaddish for those whose yahrzeit is unknown, including Holocaust victims.