On Asarah B’Teves in the year 3336, the wicked Nevuchadnetzar, king of Babylonia, laid siege to Yerushalayim, which was the first of several steps that ultimately led to the destruction of the first Beis Hamikdash (Temple). To commemorate that infamous day, the Nevi’im (Prophets)[1] instituted the ta’anis tzibbur (communal fast day) of Asarah B’Teves. This upcoming Friday, January 10, is Asarah B’Teves. In this article, we will discuss some of the halachos pertaining to the fast of Asarah B’Teves.

 1) The fast begins at alos hashachar (halachic daybreak)[2] and ends at tzeis hakochavim (halachic nightfall). Most calendars consider alos hashachar a fixed 72 minutes before sunrise, which is the common custom in this country. In the Far Rockaway/Five Towns area, this calculation of alos hashachar on January 10 is at approximately 6:06 AM. However, preferably, one should not eat after 5:51AM.[3] Tzeis hakochavim is at approximately 5:33 PM[4] (but see note).[5] This year, since the fast falls on Friday, one may not break one’s fast until after one recites or hears kiddush. Note: if one finishes davening (praying) early on Friday night, one may still not break one’s fast (with kiddush) until after tzeis hakochavim.[6]

2) Although the fast does not begin until alos hashachar, if one sleeps a sheinas keva (regular/substantial sleep)[7] on the preceding night (Thursday night), the fast is considered to have begun unless one made a t’nai (stipulation) before going to sleep (see note)[8] that one does not wish the fast to begin until morning.[9] Thus, one who wishes to wake up before alos hashachar to eat before the fast begins must make a t’nai before going to sleep on Thursday night. (See note).[10]

3) Even if one made a t’nai, one may not begin to eat a bread meal or otherwise significant meal (see note)[11] within one half-hour before alos hashachar (see note).[12]

4) All healthy men and women, as well as boys and girls over the age of bar- and bas-mitzvah, are obligated to fast.[13] One may not eat or drink even minute amounts.[14] Nevertheless, if one ate less than a k’zayis[15] or one drank less than m’lo lugmav,[16] one has not broken one’s fast and may thus still say Aneinu[17] in Sh’moneh Esrei (with the standard text)[18] and receive an aliyah[19] (see below, #11–14). One who ate more than a k’zayis or drank more than m’lo lugmav is considered to have broken one’s fast, but may still not eat or drink during the rest of the fast[20] unless one is not obligated to fast according to halacha (see below).

5) Children under the age of bar- and bas-mitzvah should not fast – even for part of the day (see note).[21] However, once children are old enough to understand the concept of a ta’anis tzibbur, their parents should train them – due to the mitzvah of chinuch[22] – to not indulge in the eating of sweets and the like.[23]

6) One who is ill (see note),[24] as well as pregnant or nursing women who do not feel well, need not fast.[25] A nursing woman who feels fine but is concerned that her milk supply will be affected negatively by her fasting should not fast (see note).[26] A postpartum woman who is not nursing need not fast during the first thirty days following childbirth.[27] If she had a cesarean section and still feels weak after thirty days have passed, she need not fast, since she is considered ill.

7) Those over bar- and bas-mitzvah who are not fasting due to health reasons may eat and drink regularly, but should not indulge in the eating of sweets and the like.[28]

8) One who needs to take a pill during the fast should swallow it without water if possible (see note).[29] If one must take the pill with food, one should consult with one’s Rav well in advance of the fast.

9) The special prohibitions of Yom Kippur (bathing, anointing oneself, and wearing shoes) do not apply to Asarah B’Teves.[30] Nevertheless, it is meritorious to not bathe (or shower) one’s body in hot water on Asarah B’Teves (but see note),[31] unless it falls on Erev Shabbos – as it does this year, in which case one may certainly bathe regularly for one’s last bathing before Shabbos. Even when it does not fall on Friday, there is no reason whatsoever to refrain from washing one’s hands, face, and feet with hot water, or from bathing in lukewarm water.[32]

10) One should not brush one’s teeth or rinse out one’s mouth on the fast.[33] If one is inordinately particular and is very disturbed by the foul taste in one’s mouth upon awaking, one may brush or rinse out one’s mouth if one is careful to tilt down one’s head to ensure that one does not swallow any water.[34]

11) In Sh’moneh Esrei of Minchah we insert the prayer of Aneinu in the b’rachah of Shema Koleinu[35] (see note 17). If one forgot to say Aneinu and already said the words Baruch Attah Hashem at the end of the b’rachah, one should not endeavor to correct oneself there. Rather, one should insert Aneinu at the end of Elokai-Netzor, before the Yih’yu L’ratzon that immediately precedes Oseh Shalom at the end of Sh’moneh Esrei .[36]

12) One who is not fasting for whatever reason may not say Aneinu in Sh’moneh Esrei, even if one had been fasting earlier in the day (see note).[37] If one is still fasting, one may say Aneinu in Sh’moneh Esrei, even if one intends to subsequently break one’s fast for whatever reason.[38]

13) One who is not fasting for whatever reason may not receive an aliyah[39] on the fast day – at Shacharis or at Minchah.[40] However, if he is called to receive an aliyah during Shacharis and the fast is on Monday or a Thursday (see note),[41] he should take the aliyah; but if he is called to receive an aliyah during Minchah, or during Shacharis when the fast is on a different day of the week, he should decline the aliyah.[42]

14) The rulings presented in the preceding paragraph apply also to one who is still fasting but intends – for whatever reason – to break his fast before it ends,[43] with one leniency: If he is called to receive an aliyah and he is embarrassed to admit that he plans to break his fast, he need not decline the aliyah (even at Minchah, and even at Shacharis on days other than Monday and Thursday), since he is still fasting at that time.[44]

[1] See Zecharyah 8:19 and Gemara Rosh Hashanah 18b.

[2] Shulchan Aruch Orach Chaim 564:1. The Bi’ur Halacha (89:1 s.v. V’im Hispaleil) points out that daybreak is not the time at which the “Morning Star” is visible; that star is visible considerably before daybreak.

[3] This is the time at which the sun is positioned 16.1 degrees below the eastern horizon. The reason for this calculation is that generally halachic times are not determined by fixed times, but by astronomical calculations.

[4] This is the time at which the sun is positioned 8.5 degrees below the western horizon. Note: Even those who act stringently on Motz’ei Shabbos and do not consider Shabbos to have ended until 72 minutes after astronomical/standard sunset may break their fast at 5:33 PM. However, it would seem that one who follows the opinion of Rabbeinu Tam (that tzeis hakochavim is 72 minutes after astronomical/standard sunset) for all purposes may not break one’s fast until 6:00 PM.

[5] One who finds fasting difficult may eat at 5:25 PM. [The explanation for this leniency is beyond the scope of this article.] For this year, see the upcoming statement in the text.

[6] See S.A. O.C. 249:4 with Rema.

[7] Generally assumed to mean at least one-half hour in bed. See S.A. O.C. 4:15-16; Mishnah Berurah 4:34; and Bi’ur Halacha s.v. David.

[8] Ohr L’tziyon 3:31:2 writes that one must make the tenai verbally. However, in Kara Alai Mo’ed (chapter 1 note 7) Rav Chaim Kanievsky is cited as ruling that although l’chatchilah (initially/preferably) one should make the tenai verbally, b’dieved (ex post facto) if one merely thought the tenai it is sufficient. Koveitz Halachos (Bein Hametzorim 2:11) writes that it would seem that the tenai need not be made verbally. See note 19 there at length.

[9] S.A. O.C. 564:1.

[10] According to some Poskim (halachic authorities) the same stringency applies to drinking. Others, however, rule more leniently with regard to drinking (see R ema ad loc.). L’chatchilah one should make a tenai to allow drinking as well. B’dieved, if one did not make a tenai, one may act leniently and drink until alos hashachar if one is accustomed to drink upon awaking (M.B. 564:6).

[11] A significant meal is defined as more than a k’beitzah (egg size) of foods of the five grains that are baked (e.g., bread, cake, cookies, some cereals); or a significant amount (the amount one normally eats when having it as a meal) of non-baked foods of the five grains (e.g., hot cereal, pasta). One may eat a significant amount of fruits, vegetables, meat, poultry, egg, and dairy products. See S.A. O.C. 232:3 and M.B. 232:34-35.

[12] Due to the obligation to daven (pray) before one eats (which applies every day, not just on fast days). See S.A. O.C. 89:3; Responsum of Rav Chaim Kanievsky (printed in Ishei Yisrael, Appendix, #86).

[13] S.A. O.C. 550:1.

[14] M.B. 567:3.

[15] An olive size amount of food; approximately the equivalent of 1 fluid ounce.

[16] A cheek-full; 1–1.3 fluid ounce, depending on the size of one’s cheek.

[17] Ashkenazic custom is that individuals say Aneinu only during Minchah; only the chazan (leader) says it during Shacharis and Minchah. Sephardic custom is that all who are fasting say it during Shacharis and Minchah (see S.A. O.C. 565:3).

[18] In contradistinction to the halacha presented at the end of note 37.

[19] M.B. 568:5.

[20] S.A. O.C. 568:15.

[21] M.B. 550:5. See also Dirshu Mishnah Berurah (ad loc.) who cites Halichos Shlomo and Orchos Rabeinu that the custom for children to complete the three fasts that immediately precede their bar- and bas-mitzvah has no halachic basis. (It should be noted, however, that Jews of German origin have a strong custom dating back at least several hundred years for children to complete the three fasts that immediately precede their bar- and bas-mitzvah.)

[22] A father is obligated in the chinuch (training) of his young children (under bar- and bas-mitzvah) to perform mitzvos that the children will be obligated to perform when they become older. (Some say a mother is also obligated in chinuch of her children; see M.B. 343:2 and 640:5) In general, the age of chinuch is 6-7, depending on the maturity of the child.

[23] Although the Mishnah Berurah rules that they may satisfy only their minimal essential food needs of bread, water, and simple foods, Birkei Yosef (O.C. 549:1) and Rav Shlomo Zalman Auerbach (cited in Halichos Shlomo - Mo’adim chapter 13 - Ta’aniyos - in Orchos Halacha note 10) write that nowadays we are not accustomed to act so stringently regarding children, and we feed them their regular meals.

[24] Even if one is not unhealthy enough to be considered a choleh (ill person) with regard to allowing acts of refu’ah (healing) on Shabbos, if one feels weaker than the general population while fasting, or if one is weak by nature, one is considered ill with regard to fasting and need not fast (Igros Moshe O.C. 44:114 and Yalkut Yosef - Kitzur Shulchan Aruch (5766) 550:12-13. Cf. Dirshu Mishnah Berurah n.e. 554:11 note 22.

[25] S.A. O.C. 554:6; Rema O.C. 550:1; M.B. 550:3. (Sephardic women who are nursing may be even more lenient; see Sh”ut Yechaveh Da’as 1:35 and Yalkut Yosef -  Kitzur Shulchan Aruch (5766) 550:10 for the particulars.) For pregnant women, the Mishnah Berurah (following the earlier Poskim) differentiates between the first forty days of pregnancy and afterwards, and rules that pregnant women may be lenient only after the first forty days have passed, unless they are in great discomfort. Contemporary Poskim note that nowadays pregnant women during the first trimester are often very uncomfortable and feel nauseated and, therefore, generally need not fast. It follows then that a woman who performed a pregnancy test and discovered she is pregnant but does not feel any discomfort must fast.

[26] See Dirshu Mishnah Berurah 550:5 n.e. end of note 9.

[27] S.A. O.C. 554:6.

[28] M.B. 550:5.

[29] The following procedure is effective: One sits and leans one’s head back, and places the pill on the back of the tongue. At the point that one starts to gag, the pill can be swallowed easily. If one cannot swallow a pill without water, one may swallow a pill with a small amount (less than 1 ounce) of water.

[30] S.A. O.C. 550:2.

[31] M.B. 550:6. See, however, Sha’ar Hatziyun 550:8 where he writes that the custom was to not bathe in hot water. In the Mishnah Berurah he writes only that a ba’al nefesh (that is, a pious person; see Rashi to Gemara Niddah 16b s.v. Ba’al Nefesh) should refrain from bathing in hot water. Koveitz Halachos - Bein Hametzorim 2:3 writes that it is good to act stringently and not bathe in hot water. See also Sha’ar Hatziyun 550:9 wherein he cites the Eliya Rabbah, who cites the Shelah, that a ba’al nefesh should not bathe in hot water even on the night preceding the fast. See also note 7 in Koveitz Halachos ad loc.

[32] Sha’ar Hatziyun 550:8.

[33] S.A. O.C. 567:3.

[34] M.B. 567:11.

[35] S.A. O.C. 565:1.

[36] S.A. O.C. 565:2; M.B. 565:7. This Yih’yu L’ratzon is sometimes referred to as the “second Yih’yu L’ratzon,” to distinguish it from the first Yih’yu L’ratzon, which is proper to say before beginning Elokai-Netzor.

[37] Bi’ur Halacha 565:1 s.v. Bein Yachid. This ruling applies to one who was not required to fast. However, one who was required to fast and mistakenly ate or drank – and is thus required to fast the rest of the day – may say Aneinu. If one ate or drank more than the amount to be considered breaking the fast (a k’zayis of food or a m’lo lugmav of beverage) , instead of saying the words b’yom tzom ta’aniseinu (on the day of our fast) , one says b’yom tzom hata’anis hazeh (on this fast day) – M.B. 568:3, as explained by Sh”ut Sheivet HaLevi (8:131).

[38] Rema O.C. 562:1; M.B. 562:7.

[39] Be called up to “read” from the Torah.

[40] S.A. O.C. 566:6.

[41] Such that there would be Torah Reading even had it not been a fast day. Note: Asarah B’Teves actually cannot fall on a Monday; the halacha is presented in Shulchan Aruch (and in this article) as Monday or Thursday since it pertains also to other fast days, some of which can fall on a Monday.

[42] M.B. 566:19.

[43] M.B. 566:20.

[44] Sha’arei Ephraim 1:10.