On the fast of the Tenth of Tevet, it is prohibited to eat and drink. In general, the laws and customs of this day are very similar to those of the Fast of Gedaliah (see p. 156).

Further reading: For more on the destruction of the Temple and the factors that precipitated it, see A Concise Guide to the Sages, p. 322.

The fast begins at dawn (roughly an hour and a half before sunrise) and ends at the emergence of the stars. The exact times for the beginning and end of the fast can be found in calendars publicized by synagogues. Once a person goes to sleep for the night, if he did not have in mind that he was going to eat before dawn, it is considered as though he accepted the fast upon himself, and he should not eat. However, many hold that he can still drink. Nonetheless, it is recommended to have in mind when going to sleep that one is not accepting the fast yet.

Males over the age of thirteen and females over the age of twelve are obligated to fast.

Pregnant and nursing women are exempt from this fast. In cases of illness, weakness, or any other problem that makes it difficult for a person to fast, one should consult with a rabbi as to whether he must fast.

There are several additions to the prayers of the day:

In the repetition of the Amida of the morning prayer service, the prayer leader recites the paragraph beginning Aneinu (“Answer us, God, answer us, on the day of our fast”), after the blessing of Redemption.

At the end of the prayer leader’s repetition of the Amida, the congregation recites penitential prayers known as Selihot. The ark is then opened for the Avinu Malkeinu prayer.

Afterward a Torah scroll is taken from the ark and is read for the congregation. The passages that are read (Exodus 32:11–14, 34:1–10) discuss Moses’ pleading to God to have mercy on the children of Israel and to forgive them for the sin of the Golden Calf.

In the afternoon prayer service, after Ashrei (Psalm 145), the Torah reading of the morning is repeated, but this time, in Ashkenazic communities, a haftara is read as well. The haftara (Isaiah 55:6 –56:8), which opens with the words: “Seek the Lord when He is found,” discusses abandoning one’s sins and drawing close to God.

In the blessing of Shema Koleinu (“Hear our voice”) in the Amida prayer, each individual adds the aforementioned Aneinu passage. In the final blessing of the Amida, the Sim Shalom formula is used rather than the Shalom Rav formula, even in communities that generally recite the Shalom Rav formula during the afternoon prayer.

During the prayer leader’s repetition of the Amida prayer, he recites the paragraph beginning Aneinu after the blessing of Redemption. Prior to the blessing of Sim Shalom, he recites the passage commemorating the priestly benediction. In Israel it is customary that if the congregation is praying in the late afternoon, the priests recite the priestly benediction (Numbers 6:24–26).

After Tahanun, the congregation adds the Avinu Malkeinu prayer, which is recited with the ark open.

The Fast of Tevet is the only public fast that can occur on a Friday. In such a case, the prayers of Kabbalat Shabbat and the Friday evening service are recited more quickly than usual, in order to allow the congregants to get home and break the fast as soon as possible.