Tenth of Tevet

The Tenth of Tevet (Asara B'Tevet) commemorates the beginning of the Babylonian siege of Jerusalem by Nebuchadnezzar in 588 BCE, which ultimately led to the destruction of the First Temple. It is a minor fast day from dawn to nightfall. In Israel, it is also designated as Yom HaKaddish HaKlali, a general memorial day for Holocaust victims whose date of death is unknown.

The Tenth of Tevet is the only minor fast that can never be postponed — if it falls on Friday, the fast is observed even into Shabbat. Some authorities consider it potentially the most severe of the minor fasts because the prophet Ezekiel was specifically commanded to record the date of the siege, underscoring its significance.