Why Asara b'Teves is Different

Q. The Beis Yosef (OC 550) quotes Sefer Avudraham (a work authored by the 14th century Spanish posek, Rav David Avudraham,) that if Asara B’Teives would fall on Saturday, the fast would be observed on Shabbos. (In practice, once the calendar was fixed by Hillel Ha'Sheini, Asara B’Teives cannot fall on Shabbos.) However, other public fasts days that fall on Shabbos are postponed to Sunday. Why is Asara B’Teives different than other fast days?

A. The Avudraham writes that Asara B’Teiveis is not delayed because the pasuk in Yechezkel 24:2 states that the Babylonians laid siege on Yerushalayim “b’etzem ha’yom ha’zeh” (In the midst of this day). This phrase indicates the significance of that particular date, and therefore the fast is never delayed.  The same expression appears in the Torah when describing Yom Kippur (Vayikra 23:29), which also is never postponed. In spite of this explanation, the Beis Yosef questions why Asara B’Teiveis is unique?

Rav Chaim Brisker (Chidushei HaGrach – Rosh Hashanah 18b) offers the following explanation: When necessary, a fast may take place on Shabbos. This can be demonstrated from the fact that a taanis chalom (a fast to annul a disturbing dream) is observed on Shabbos, because the fast is most effective the same day as the dream. If so, why are the fasts of Shiva Assar B’Tamuz and Tisha B’Av postponed when they fall on Shabbos? Rav Chaim responds that the Navi in Zecharia (8:19) refers to Shiva Assar B’Tamuz as the fast of the 4th month and Tisha B’Av as the fast of the 5th month (see Rosh Hashana 18b). Since the Navi identifies the fast days by the month and not the calendar date, it appears that Tamuz and Av were selected for fasting because they were periods of tragedy, and the specific dates were chosen only to establish uniformity. When the fasts fall on Shabbos, the fasts are delayed because the month remains the same, and the day of the month is of secondary importance. In contrast, regarding Asara B’Teives, since Yechezkal emphasized, “in the midst of this day”, it is clear that the tenth of Teives is of special significance, and therefore the taanis is observed even on Shabbos, just as a taanis chalom is observed on Shabbos.

______________________________________________________

The Gerald & Karin Feldhamer OU Kosher Halacha Yomis is dedicated to the memory of Rav Yisroel Belsky, zt"l, who served as halachic consultant for OU Kosher for more than 28 years; many of the responses in Halacha Yomis are based on the rulings of Rabbi Belsky. Subscribe to the Halacha Yomis daily email here.