Asara B’Tevet / עֲשָׂרָה בְּטֵבֵת, the tenth day of the Hebrew month of Tevet, is a minor fast day in Judaism. The fast commemorates the siege of Jerusalem.
Although the Tenth of Tevet is an annual observance on the Hebrew calendar, the date can fall during December or January on the Gregorian calendar. In some Gregorian years, there is no observance of the fast. In other Gregorian years, the fast is observed twice.
For example, the Tenth of Tevet does not occur at all in during the Gregorian year 2024. The fast for Hebrew year 5785 will be observed in January 2025, and the Asara B’Tevet 5786 observance of the fast will be in occur in December 2025.
To illustrate further, consider the following 8-year table:
| Hebrew Date | Gregorian Date |
|---|---|
| 10 Tevet 5780 | Tuesday, January 7, 2020 |
| 10 Tevet 5781 | Friday, December 25, 2020 |
| 10 Tevet 5782 | Tuesday, December 14, 2021 |
| 10 Tevet 5783 | Tuesday, January 3, 2023 |
| 10 Tevet 5784 | Friday, December 22, 2023 |
| 10 Tevet 5785 | Friday, January 10, 2025 |
| 10 Tevet 5786 | Tuesday, December 30, 2025 |
| 10 Tevet 5787 | Sunday, December 20, 2026 |