Tisha B'Avתִּשְׁעָה בְּאָב

Tisha B’Av (Hebrew: תשעה באב or ט׳ באב, “the Ninth of Av,”) is an annual fast day in Judaism, named for the ninth day (Tisha) of the month of Av in the Hebrew calendar. The fast commemorates the destruction of both the First Temple and Second Temple in Jerusalem, which occurred on the same Hebrew calendar date, 490 years apart by the traditional count and about 655 years apart by conventional historical dating. Tisha B’Av is never observed on Shabbat. If the 9th of Av falls on a Saturday, the fast is postponed until the 10th of Av. Tisha B'Av is regarded as the saddest day on the Jewish calendar and the climax of a season of mourning. Besides the two Temple destructions, tradition links the date to a cluster of national calamities: the decree (Numbers 14) that the Exodus generation would wander forty years and not enter the Land, the fall of Betar and crushing of the Bar Kokhba revolt (135 CE), and the subsequent plowing-under of Jerusalem; later tradition adds expulsions and other catastrophes to the day's memory. The fast is the culmination of the Three Weeks of mourning that begin on the 17th of Tammuz and of the more intense Nine Days that begin on the 1st of Av. Its themes are exile, loss, destruction, and the yearning for restoration. Observance and emphasis vary by movement: Reform Judaism has historically downplayed or not observed the day, given its theological focus on the present-day Diaspora over a restored Temple cult.

Tisha B'Av falls on the 9th of Av in the Hebrew calendar, which lands in July or August on the Gregorian calendar. It is a roughly 25-hour fast running from sunset on the eve of the 9th through nightfall the following evening. The day is never observed on Shabbat: when the 9th of Av falls on a Saturday, the fast is postponed (nidcheh) to the 10th of Av on Sunday. The same date and observance apply in both Israel and the Diaspora, since fast days, unlike the pilgrimage festivals, are not extended to a second day in the Diaspora.

The central reading is the Book of Lamentations (Eicha) in its entirety, all five chapters, chanted chiefly at the evening (Maariv) service after nightfall and, in some communities, again in the morning. Eicha is sung to its own distinctive, mournful cantillation, the Eicha trope, which is heard in full only once a year; in the most common Ashkenazi tradition each verse characteristically begins in a major mode and resolves into its relative minor for a sorrowful effect, and the reader chants seated low to the ground. This Eicha mode also colors the haftarah on Tisha B'Av morning and on the preceding Shabbat Chazon, and the same melody is famously borrowed on Purim for the perilous verses of Megillat Esther. In the morning (Shacharit) the Torah reading is Deuteronomy 4:25-40 and the Haftarah is Jeremiah 8:13-9:23. In the afternoon (Mincha) the Torah reading is Exodus 32:11-14 and 34:1-10 (the standard fast-day passage with the Thirteen Attributes of Mercy), and the Haftarah is Isaiah 55:6-56:8 in Ashkenazi practice. Some Sephardic communities instead read Hosea 14:2-10 with Micah 7:18-20 at Mincha and read the Book of Job on the morning of Tisha B'Av, and German (Yekke) custom recites the morning readings to a plain melancholic melody rather than full cantillation.

Five traditional afflictions are observed: no eating or drinking (a full fast), no washing or bathing, no anointing with creams or oils, no wearing of leather shoes, and no marital relations. Torah study is largely avoided because it brings joy, with the exception of distressing texts such as Lamentations, the destruction passages of Jeremiah, the Book of Job, and Talmudic and midrashic accounts of the Temple's fall. After the evening and morning services the congregation recites kinnot (liturgical dirges), often by dimmed light; worshippers sit on the floor or on low stools as mourners, and the ark curtain (parochet) is often removed or the lights dimmed. Tallit and tefillin are typically not worn at the morning service but are donned at Mincha in the afternoon, when the intensity of mourning eases somewhat after midday (chatzot). The pre-fast meal (seudah hamafseket) traditionally features mourners' foods such as eggs or lentils, sometimes dipped in ashes, eaten while seated on the ground, and it is also customary to visit cemeteries. Specific practices vary by community and rite.