1. Pinner Shul
  2. Questions for Rabbi Kurzer
  3. Asara B’Tevet on a Friday

N.B. the following has been written for Asara B’Tevet 5784 (Dec. 2023) – the times would be different in another year.


Why is Asara B’Tevet the only fast day that we observe on a Friday?  How does it work practically to avoid clashing with the laws of Shabbat?


The end of the book of Melachim (II Kings) tells of Nevuchadnezar laying siege to Jerusalem on the 10th of Tevet (the 10th month).  This siege ultimately led to the destruction of the First Temple and is one of the key parts of our continued mourning for the loss of both holy Temples.

Before we look at why we do fast, let us first begin by considering why we might not fast on a Friday – there are a number of reasons brought in various sources.  Firstly, the Rokeach (Shabbat ch. 36), a 13th century German Kabbalist, says that erev Shabbat (Friday) is like ShabbatRabbi Soloveitchik, who started life in eastern Europe and moved to America in 1932, commented, “it is not for the Sabbath that my heart aches, it is for the ‘eve of the Sabbath.’ There are Sabbath-observing Jews in America, but there are not ‘erev-Sabbath’ Jews who go out to greet the Sabbath with beating hearts and pulsating souls.” (‘On Repentance’ p.88).  We see that there is something special about a Friday and how important it is for us to treat the day as such generally.

The Medrash Tanchuma (Bereishit 3) presents a different reason and says that we move fast days from Shabbat because there is much to prepare for Shabbat and we should be busy doing that rather than spending a long time on selichot and the like.  Part of honouring Shabbat (“kavod”) is the extensive preparation we do in anticipation of this special day.

Nevertheless, although the Shulchan Aruch (OC 550:3) writes that fasts other than Yom Kippur are pushed off if they fall on Shabbat, the Rema clarifies that there are four fasts associated with mourning the destruction of the Temples and if they fall on Friday then we fast as normal.  These four fasts are delineated by the prophet Zechariah (8:19) and are on the 17th Tamuz, 9th Av, 3rd Tishrei and 10th Tevet.  In practice, Asarah B’Tevet is the only one of the four that can fall on a Friday and the only one that cannot fall on Shabbat.  Other fasts that may be moved from a Friday include Ta’anit Ester, a fast on a parent’s yahrtzeit (a common practice) or fasting on 7th Adar, often observed by a chevra kadisha.

(Interestingly, the Aruch HaShulchan (OC 549:2) in a long piece discussing the details of Asarah B’Tevet, quotes an earlier source that we would fast on Asarah B’Tevet even if it fell on Shabbat!  He bases this on the pasuk in Yechezkel which uses the phrase “עֶצֶם הַיֹום הַזֶה”, meaning “this very day”, a phrase similar to that used about Yom Kippur.  Many others disagree with this and, as noted above, it makes no practical difference in the calendar we use.) In practice, there a few things to be aware of in the winter and on a Friday.

  • The mishna (Taanit 2:1) tells us that the main goal of a fast is not to afflict ourselves but to use the opportunity to analyse our actions and see how we can improve.  This applies whether one is able to fast or not.
  • The fast begins at 6:14am, however, if one wants to eat in the morning before that time, one should ideally have this in mind the night before.
  • One may shower, shave and prepare as usual for Shabbat.
  • Shacharit is like a normal fast day, including selichot.
  • At Mincha, we read from the Torah and aneinu is included in the amida.  However, because it is Friday, neither tachanun nor avinu malkeinu are said.
  • Although Shabbat begins at 3:39pm, the fast does not end until 4:42pm and therefore we do not make kiddush in Shul and one should wait until that time to make kiddush at home.

May we all merit to see our redemption speedily in our days.

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