Overview
- Asarah B’Teves commemorates the start of Nebuchadnezzar’s siege of Jerusalem and is observed as a public minor fast.
- The fast begins at dawn, and healthy adults—including girls from 12 and boys from 13—are obligated under Shulchan Aruch and Mishnah Berurah.
- Pregnant or nursing women and the sick are not required to fast on minor fasts, though individual circumstances should be discussed with a rabbi.
- Practical guidance includes permitting showers, discouraging hot water for the especially scrupulous, and generally avoiding tooth brushing or mouthwash unless used carefully to prevent swallowing.
- Liturgical practice adds Selichot and Avinu Malkeinu at Shacharit and Aneinu at Mincha, with instructions not to repeat the Amidah if Aneinu is omitted and to skip Aneinu when not fasting.