Fasting on Friday?
Asarah B’Teves: Not Your Ordinary Fast Day
One of the fascinating characteristics of 5781 is that the Taanis Tzibbur of Asarah B’Teves (the 10th of Teves) will fall out on Friday. Or to be precise, this Friday. This remarkable status of a ‘Friday Fast’ is actually exclusive to Asarah B’Teves – as it is the only one that we do actually observe as a communal fast on a Friday.
Although to many the only notable aspect of Asarah B’Teves is that it is by far the shortest fast day in the Jewish calendar for anyone in the Northern Hemisphere (my heartfelt sympathies to the South Americans, So’Africans, Aussies, and Kiwis), nonetheless, it turns out that the Fast of Asarah B’Teves is actually quite unique. Indubitably, to maintain this distinction of being the only Taanis Tzibbur that we actually do observe on Friday, there is much more to the Fast of Asarah B’Teves than meets the eye. Indeed, upon closer examination, Asarah B’Teves has several exceptional characteristics that are not found in any other fast day.
Why This Fast?
The reason given for fasting on Asarah B’Teves is that it is the day that the wicked Babylonian king Nevuchadnetzar started his siege of Yerushalayim, foreshadowing the beginning of the end of the first Beis Hamikdash, which culminated with its destruction on Tisha B’Av several years later. Therefore, Chazal declared it a public fast, one of four public fast days that memorialize different aspects of the catastrophes and national tragedies associated with the destruction of both Batei HaMikdash.
A Friday Fast
However, of these four public fast days, as mentioned previously, only Asarah B’Teves is actually observed on a Friday. Proof to Asarah B’Teves’ exceptionality can perhaps be gleaned from the words of Yechezkel HaNavi referring to Asarah B’Teves, that the siege of Yerushalayim leading up to the destruction of the first Beis HaMikdash transpired “B’Etzem HaYom HaZeh – in the middle of this day,” implying that the fast must always be observed on that exact day, no matter the conflicting occurrence. This would help explain why it is fully observed on Friday, with no dispensation given.
Yet, this uniqueness is fairly interesting, as there is a whole debate in the Gemara about how to conduct fasts on a Friday, when we must also take kavod Shabbos into account, implying that it is a common occurrence. However, according to our calendar, a communal Friday fast is only applicable with Asarah B’Teves, and it actually does occur quasi-frequently. The last few times Asarah B’Teves fell out on a Friday were in 1996, 2001, 2010, and 2013; the latter of which, quite appropriately, coincided with a “Yerushalmi Blizzard.”
Asarah B’Teves is next expected to occur on a Friday in 2023 (5784), 2025 (5785), 2034 (5795), and 2037 (5798). In another interesting calendarical twist, but not the Jewish calendar, due to the differences between the Jewish lunar-based year and the Gregorian solar-based year, this fast, curiously (and perhaps appropriately) falling out on December 25th, is actually the second Asarah B’Teves fast to occur in 2020. The first was back on January 7th (anyone remember that B.C. – Before Covid-19?).
Halachos of a Friday Fast
The halachos of a Friday fast generally parallel those of a regular fast day; including Aneinu and the Kriyas HaTorah of “Vayechal” twice (along with the haftarah of “Dirshu” at Mincha), albeit with no Tachanun or Avinu Malkeinu at Mincha, as it is Erev Shabbos. In fact, even though there is some debate in the Rishonim as to the Gemara’s intent that “Halacha – Mesaneh U’Mashlim, a Friday fast should be completed” whether or not one may be mekabel Shabbos early and thereby end the fast before nightfall, nonetheless, the halacha follows the Shulchan Aruch and Rema that since Asarah B’Teves is a public fast (Taanis Tzibbur) and not a Taanis Yachid, one must fast the whole day and complete it at nightfall (Tzeis HaKochavim) before making Kiddush.
There are many Poskim who maintain that it is preferable to daven Maariv somewhat earlier than usual on this Friday night, to enable making Kiddush, and breaking the fast exactly at Tzeis HaKochavim.On the other hand, there are those who maintain that if one generally waits until Zman Rabbeinu Tam (Shiur 4 Mil, commonly observed as 72 minutes after Shkiya) to break his fast, he should do so as well this Erev Shabbos Asarah B’Teves, but nonetheless should make Kiddush immediately at the Zman. Some maintain that it is preferable to begin the Leil Shabbos Seudah directly with Kiddush and only recite Shalom Aleichem and Eishes Chayil after being somewhat satiated and relaxed.
Three Day Fast?
Another fascinating and unique aspect of this fast, is that according to the special Selichos prayers recited on Asarah B’Teves, we are actually fasting for two other days of tragedy as well; the 8th and 9th of Teves. In fact, and although in his Beis Yosef commentary the great Rav Yosef Karo, notes that he has never seen nor heard of anyone fasting on these days, nevertheless, both the Tur and in his own later Shulchan Aruch, Rav Karo asserts that it is proper to try to fast on all three days. However, it is important to note that of the three, only Asarah B’Teves was actually mandated as a public fast day.
The 8th of Teves
On the 8th of Teves, King Ptolemy II (285-246 B.C.E.) forced 72 sages separately to translate the Torah into Greek (the Septuagint). Although miracles guided their work and all of the sages made the same slight but necessary amendments, nevertheless this work is described as “darkness descending on the world for three days,” as it was now possible for the uneducated to possess a superficial, and frequently flawed understanding of the Torah, as well as providing the masses with a mistaken interpretation of true morality.
The 9th of Teves
Although several decisors, following the MegillasTaanis,write that the reason for fasting on the 9th of Teves is unknown, nonetheless many sources, including the Kol Bo and the Selichos recited on Asarah B’Teves, as well as many later authorities, explain that this is the day on which Ezra HaSofer, as well as possibly his partner in rebuilding the Jewish Yishuv in Eretz Yisrael after the 70 year Galus Bavel, Nechemiah, died. Ezra, the Gadol HaDor at the beginning of the time of the Second Beis HaMikdash, had a tremendous impact upon the nascent returning Jewish community of Eretz Yisrael. He drastically improved the spiritual state of the Jewish people and established many halachic takanos, many of which still apply today. With his passing, the community started sliding from the great spiritual heights Ezra had led them. Additionally, since Ezra was the last of the prophets, his passing signified the end of prophecy.
Other sources attribute fasting on this day to the passings of other specific Tzaddikim on this day, including the enigmatic Shimon HaKalphus and Rav Yosef HaNaggid, or to the birth of ‘Oso HaIsh’, the founder of Christianity, in whose name myriads of Jews over the millennia were R”l murdered.  The Sefer HaToda’ah posits that it’s possible that Chazal’s expression of “darkness descending on the world for three days” alludes to the triple woes of these three days: the 8th, 9th, and 10th of Teves.
A Shabbos Fast?!
The third and possibly most important attribute of Asarah B’Teves is that according to the Abudraham, if Asarah B’Teves would potentially fall out on Shabbos, we would all actually be required to fast on Shabbos! (Notwithstanding that with our calendar this is an impossibility.) He cites proof to this from the words of Yechezkel referring to Asarah B’Teves that the siege transpired “B’Etzem HaYom HaZeh,” implying that the fast must always be observed on that exact day, no matter the conflicting occurrence – not only Friday, but even on Shabbos.
Yet, the Abudraham’s statement is astounding, as the only fast that halachically takes precedence over Shabbos is Yom Kippur, the only Biblically mandated fast. How can one of the Rabbinic minor fasts push off the Biblical Shabbos? Additionally, Asarah B’Teves commemorates merely the start of the siege, and not any actual destruction. How can it be considered a more important fast than Tisha B’Av, which commemorates the actual destruction and loss of both of our Batei HaMikdash, which get pushed off when it falls on Shabbos?
In fact, the Beis Yosef questions this declaration of the Abudraham, stating that he “does not know how the Abudraham could know” such a ruling. As an aside, this does not seem to be the actual halacha, as other Rishonim, including Rashi and the Rambam, as well as the Tur and Shulchan Aruch and later poskim explicitly rule, that if Asarah B’Teves falls out on Shabbos it gets pushed off. 
Commencement Is Catastrophic
Several authorities, including Rav Yonason Eibeschutz and the Bnei Yissaschar, understand the Abudraham’s enigmatic statement as similar to the famous Gemara in Taanis (29a) regarding Tisha B’Av. It seems that historically the Beis HaMikdash only started to burn toward the end of the 9th of Av (Tisha B’Av) and actually burned down on the 10th. Yet, Chazal established the fast on the 9th, since “Aschalta D’Paranusah Adifa,” meaning that the beginning of a tragedy is considered the worst part. Likewise, they maintain that since the siege on Asarah B’Teves was the harbinger to and commencement of the long chain of tragedies that ended with the Beis HaMikdash in ruins and the Jewish people in exile, its true status belies the common perception of it as a minor fast, and potentially has the ability to push off Shabbos.
Indeed, the MidrashTanchuma teaches that it was already fitting for the BaisHaMikdash to actually be destroyed on Asarah B’Teves, but Hashem, in His incredible mercy, pushed off the destruction to the summertime, so that Klal Yisrael would not have to be exiled in the cold. Hence, Asarah B’Teves’s role as the ‘beginning of the end’ underlies the severity of this fast day.
The famed Chasam Sofer takes this a step further. He wrote that the reason Chazal established a fast for the siege on Asarah B’Teves, as opposed to every other time Yerushalayim was under siege over the millennia, is that on that day in the Heavenly Courtroom it was decided that the Bais HaMikdash was to be destroyed a few years hence. There is a well known Talmudic dictum that any generation in which the Beis HaMikdash has not been rebuilt is as if it has been destroyed again. Therefore, he explains, every Asarah B’Teves the Heavenly Court convenes and decrees a new Churban. He adds though that, conversely, a proper fast on Asarah B’Teves has the potential to avert future Churbanos.
Accordingly, we are not fasting exclusively due to past calamities, but rather, similar to a Taanis Chalom, a fast for a dream, we are fasting to help prevent a tragedy from occurring. The Chasam Sofer even refers to such a fast as an oneg, a delight, as our fasting will help stave off potential future catastrophes. That is why the fast of Asarah B’Teves, even though it is considered a minor fast, nonetheless has the potential to possibly override Shabbos. These explanations would also certainly elucidate why we would fast on a Friday for Asarah B’Teves.
The Rambam famously exhorts us to remember the real meaning underlying a fast day. It’s not just a day when we miss our morning coffee! The purpose of fasting is to focus on the spiritual side of the day and use it as a catalyst for inspiration towards Teshuva. In this merit may the words of the Navi Zechariah, “The Fast of the Fourth (month, 17th of Tamuz), the Fast of the Fifth (month, Tisha B’Av), the Fast of the Seventh (month, Tzom Gedalyah), and the Fast of the Tenth (month, Asarah B’Teves) shall be (changed over) for celebration and joy for the household of Yehuda” be fulfilled speedily and in our days.
This article was written L’Iluy Nishmas the Ohr Somayach Rosh HaYeshiva - Rav Chonoh Menachem Mendel ben R’ Yechezkel Shraga and R’ Chaim Baruch Yehuda ben Dovid Tzvi and l’zechus Shira Yaffa bas Rochel Miriam v’chol yotzei chalatzeha for a yeshua sheleimah teikif u’miyad!
For any questions, comments or for the full Mareh Mekomos / sources, please email the author: firstname.lastname@example.org.
Rabbi Yehuda Spitz serves as the Sho’el U’Meishiv and Rosh Chabura of the Ohr Lagolah Halacha Kollel at Yeshivas Ohr Somayach in Yerushalayim. He also currently writes a contemporary halacha column for the Ohr Somayach website titled “Insights Into Halacha”. http://ohr.edu/this_week/insights_into_halacha/.
His first English halacha sefer, discussing the myriad halachos pertaining to the foods that we eat, is currently at the printer and is due out shortly.
See Meiri (Megillah 2a), Abudraham (Hilchos Taanis), Magen Avraham (O.C. 550:4), Ba’er Heitiv (ad loc. 4), Aruch Hashulchan (ad loc. end 2), and Mishnah Berurah (ad loc. 10). Although the Erev Pesach Taanis Bechorim can also technically fall out on a Friday, nevertheless, it is not a true communal fast, as it is not incumbent upon all of Klal Yisrael, rather exclusive to firstborns, of whom the vast majority exempt themselves with a siyum - see Aruch Hashulchan (O.C. 470:5) and Mishnah Berurah (ad loc. 10). Moreover, the common minhag is that when Erev Pesach occurs on Erev Shabbos, like it does this year, 5781 – the Taanis Bechorim is actually observed on Thursday. See Terumas Hadeshen (126), Shulchan Aruch and Rema (O.C. 470:2), Ben Ish Chai Ben Ish Chai (Year 1 Parashas Tzav, Halachos Im Chal Erev Pesach B’Shabbos Kodesh 1), and Rav Yosef Eliyahu Henkin’s authoritative Ezras Torah Luach (reprinted in Shu”t Gevuros Eliyahu O.C. vol. 1:126, 7). However, as noted by the Tur and Shulchan Aruch (O.C. 249:3; citing Gemara Eruvin 40b and Yerushalmi Taanis Ch. 2, Halacha 12), Anshei Maaseh would have the custom of fasting every Erev Shabbos.
Melachim II (Ch. 25:1), Yirmiyahu (Ch. 52:4), Yechezkel (Ch. 24:1-2). Interestingly, it seems that Yechezkel HaNavi’s wife also died on Asarah B’Teves, as the same prophecy on that day continues with his wife’s passing (Ch. 24:15-19). See Gemara Moed Kattan (28a) and Ya’aros Dvash (vol. 2, Drush 12 s.v. ulefi zeh).
See Zecharia (Ch. 8:19), Gemara Rosh Hashana (18b), Rambam (Hilchos Taaniyos Ch. 5 1- 5) and Tur and Shulchan Aruch (O.C. 549 and 550).
Yechezkel (Ch. 24:2).
See Rambam (Hilchos Taaniyos Ch. 5:5), Abudraham (ibid.), Beis Yosef (O.C. 550 s.v. u’mashekasav v’im), Rema (ad loc. 3), Magen Avraham (ad loc. 6), and Mishnah Berurah (ad loc. 4). Although technically speaking, if other fasts (with the possible exception of Taanis Esther) would fall out on Friday, an impossibility in our calendar, we would also have to fast.
Gemara Eiruvin (41a).
Yes, this author is familiar with the ‘Coincidences’ involved with that memorable Yerushalayim snowstorm. According to the Targum (Rav Yosef) to Divrei Hayamim, ‘Yom Hasheleg,’ ‘The Day of Snow’ that Benayahu ben Yehoyada “smote the lion in the pit” (Shmuel II, Ch. 23:20 and Divrei Hayamim I, Ch. 11:22; see also Gemara Brachos 18a), is none other than Asarah B’Teves! Additionally, since it was a fast, the haftarah read by Mincha included the apropos verse (Yeshaya Ch. 55:10) referring to “Ka’asher Yei’reid Hageshem Vehasheleg min Hashamayim, when the rain and snow fall from the heavens.” Furthermore, that day’s Daf Yomi was Yoma 35, which includes the famous account of Hillel almost freezing to death on the roof of Shmaya and Avtalyon’s Beis Midrash, while trying to listen to their teaching “Divrei Elokim Chaim,” when he could not afford the admission fee. That day was described by the Gemara as an Erev Shabbos in Teves, that a tremendous amount of snow (three amos) fell upon him from the heavens. Moreover, this incident ostensibly occurred in Yerushalayim, as it is well known that Shmaya and Avtalyon, the Gedolei HaDor, lived in Yerushalayim. [See Mishnayos Ediyus (Ch. 1:3 and Ch. 5:6), Gemara Brachos (19a), Shabbos (15a), and Yoma (71b).] Thanks are due to Rabbi Dovid Alexander for his paper on these ‘Coincidences.’
Well, perhaps not so curious, but possibly rather apropos. You see, according to the Selicha for Asarah B’Teves that starts with the word Ezkerah, generally attributed to Rav Yosef Tov-Alem (Bonfils), a unique aspect of Asarah B’Teves is that we are actually fasting for two other days of tragedy as well; the 8th and 9th of Teves. According to the Megillas Taanis, regarding the 9th of Teves, “lo noda bo eizo hi hatzara she’eera bo,” the reason for the fast is unclear. One theory posited over the centuries is that the real reason for fasting is that the 9th of Teves is the true birthday of ‘Oso HaIsh’, in whose name myriads of Jews over the millennia were R”l murdered. The origin of this claim seems to be the 12th century Sefer HaIbur by Rav Avraham bar Chiya (pg. 109). In fact, the Netei Gavriel (Hilchos Chanuka, Inyanei Nittel, pg. 416) cites that some say that Nittel, the name used for the Christian December holiday, actually stands for Nolad Y eishu T es L’Teves. This is discussed further in the article.
Interestingly, in 2022 there is no Asarah B’Teves. It is set to next occur on December 14, 2021 and the following one on January 3, 2023. This is because the corresponding Jewish year, 5782, is a leap year with an added Chodesh Adar; hence there are 384 days between the two fasts of Asarah B’Teves – 19 days longer than the solar/Gregorian calendar year. Thanks are due to R’ Abraham Schijveschuurder for pointing out this calendar quirk.
However, even those who advise not to bathe on a regular fast day, nevertheless allow one to do so on a Friday fast L’Kavod Shabbos, with hot water as usual. See Bach (O.C. 550:3; although cited by both the Ba’er Heitiv and Mishnah Berurah as the source for this rule, nevertheless, this author has been unable to locate where exactly the Bach states an explicit Erev Shabbos exception for bathing), Elyah Rabba (ad loc. 2), Ba’er Heitiv (ad loc. 3), Shu”t Ksav Sofer (O.C. 100), Shulchan HaTahor (249:4), Mishnah Berurah (ad loc. end 6), and Shu”t Siach Yitzchak (247).
Parashas Ki Sisa (Shemos Ch. 22:11). Haftarah is Yeshaya (Ch. 55:6).
See Abudraham (ibid.), Maharil (Hilchos Taaniyos 17), Rema (O.C. 550:3 and 566:1), Magen Avraham (O.C. 550:6), Yad Efraim (ad loc.), and Mishnah Berurah (550:11 and 566:5). The halacha is not like the Shibolei Haleket (263, Hagahos; as cited by the Agur, 880, and later the Beis Yosef, ibid.) who maintains that we also do not lein the special Fast Day Kriyas HaTorah at Mincha Erev Shabbos.
Although the Gemara (Eruvin 41a; also in Midrash Tanchuma, Bereishis 2) concludes “Halacha - Mesaneh U’Mashlim,” even so, there are many Rishonim [most notably Tosafos (ad loc. 41b s.v. v’hilchasa), the Rashba, and Ritva (ad loc.)] who understand this dictum to mean that one may conclude his Erev Shabbos fast at Tzeis HaKochavim, even though it means he will enter Shabbos famished (a situation that is normally disfavored), and not that one must conclude his fast on Friday night at Tzeis HaKochavim. An additional shittah is that of the Raavad (Sefer HaEshkol, vol. 2, pg. 18; cited by the Beis Yosef, O.C. 550:3), who maintains that “mashlim” in this instance is referring to completing the fast by Shkiya, as otherwise it will infringe upon Tosefes Shabbos. A further complication is that this also may depend on whether one is fasting for personal reasons (Taanis Yachid) or an obligatory public fast (Taanis Tzibbur). The Rema (O.C. 249:4) concludes that for a Taanis Yachid one may rely upon the lenient opinions and end his fast after he accepted Shabbos, prior to Tzeis HaKochavim (especially if he made such a stipulation before commencing his fast), yet for a Taanis Tzibbur, he rules that we follow the Rishonim who mandate strict interpretation of the Gemara, and we must fast until actual nightfall on Friday night. It is debatable whether the Shulchan Aruch is actually fully agreeing with this approach or not. See explanation of the Mishnah Berurah (ad loc. 21 and Biur Halacha s.v. v’im) at length. This has since become normative halacha. See next footnote.
See Shulchan Aruch and Rema (O.C. 249:4), based on the Rosh (Taanis Ch. 2:4) and Maharil (Shu”t 33); Magen Avraham (ad loc. 8), Bach (ad loc. end 6), Ba’er Heitiv (ad loc. 7), Elyah Rabba (ad loc. 10), Korban Nesanel (Taanis, end Ch. 2:60), Shulchan Aruch HaRav (ad loc. 12), Kitzur Shulchan Aruch (121:6), Ben Ish Chai (Year 2, Parashas Lech Lecha 23), Aruch Hashulchan (ad loc. 10), Mishnah Berurah (ad loc. 21 and Biur Halacha s.v. v’im), Kaf Hachaim (ad loc. 29 and 31), Shu”t Yabea Omer (vol. 6, O.C. 31), Shu”t Yechaveh Daas (vol. 1:80), Netei Gavriel (Hilchos Chanuka, Shu”t 14), Yalkut Yosef (Kitzur Shulchan Aruch, O.C. 249:7 and 559:25), and Rav Mordechai Eliyahu’s Darchei Halacha glosses to the Kitzur Shulchan Aruch (121:5). The Netei Gavriel adds that B’shaas Hadchak and l’tzorech gadol one may be mekabel Shabbos early and rely on the lenient opinions, as long it is after nightfall according to several opinions (meaning, an earlier Zman of Tzeis HaKochavim than the faster would usually observe).
See Shulchan HaTahor (249:13) who writes that usually it is assur to complete a Friday fast until Tzeis HaKochavim, even an obligatory fast, as it is an affront to Kedushas Shabbos; rather, he maintains that one should be mekabel Shabbos early and have his seudah before nightfall. Yet, in his explanations (Zer Zahav ad loc. 4) he maintains that regarding Asarah B’Teves on Friday, since we are beholden to follow the ruling of the Rema, one should still be mekabel Shabbos early, and daven Maariv earlier than usual, to enable us to end the fast with making Kiddush at the exact zeman of Tzeis HaKochavim. This is also cited by the Netei Gavriel (Hilchos Chanuka, Ch. 63:6). The Steipler Gaon (cited in Orchos Rabbeinu, new version, vol. 1, pg. 203:7 and vol. 2, pg. 200:8) was noheig this way, that in his shul on Asarah B’Teves on a Friday, they davened Maariv earlier than usual and announced that everyone should repeat Kriyas Shema. It is also mentioned (Orchos Rabbeinu ibid. and vol. 3, pg. 160:5) that this was the Chazon Ish’s shittah as well, regarding any taanis, that Maariv should be davened somewhat earlier than usual, with Kriyas Shma repeated later on (the Chazon Ish held to start from 30 minutes after Shkiya, instead of his usual shittah of 40 minutes). This idea is also found in the Matteh Efraim (602:29), albeit regarding Tzom Gedalia, not to tarry extraneously regarding Maariv on a Motzai Taanis. He explains that there is no inyan of tosefes (adding extra time to) on a fast day aside from the Biblically mandated Yom Kippur, and therefore it is worthwhile to synchronize the ending of Maariv with the fast ending, and not wait for the full Tzeis Hakochavim to start Maariv as is usually preferred. Rav Shmuel Halevi Wosner (Shu”t Shevet Halevi vol. 6:72 and vol. 10:81 and Halichos Shevet Halevi Ch. 21:4, pg. 172) ruled this way as well, that it is proper to daven Maariv earlier on a standard fast day, shortly after Bein Hashmashos of the Gaonim’s shittah, in Eretz Yisrael approximately 20 minutes after Shkiya. It is known that Rav Yosef Shalom Elyashiv (Hanhagos Rabbeinu pg. 308:133, and in his Talmid, Rav Nochum Eisenstein’s Dvar Halacha, #160, Parashas Vayigash 5781) as well, would daven Maariv on Motzai Taanis, even Motzai Tisha B’Av, twenty minutes after Shkiya (instead of his usual thirty minutes). Rav Shmuel Salant, long time Rav of Yerushalayim in the late 1800s, ruled similarly (Toras Rabbeinu Shmuel Salant zt”l vol. 1, pg. 102:5) that on a Motzai Taanis, Maariv should be recited earlier than usual, in Yerushalayim from 10 minutes after Shkiya, and making sure Kriyas Shema is repeated afterwards. See also Halichos Even Yisrael (Moadim vol. 1, pg. 370:39 and vol. 2, pg. 145:1) that even on Motzai Yom Kippur and Motzai Tisha B’Av (which have a din of tosefes), Rav Yisrael Yaakov Fischer held to daven Maariv 20 minutes after Shkiya.
See the Sanzer Dayan, Rav Yitzchak Herskovitz’s Shu”t Divrei Ohr (vol. 2:47), as well as the Klausenberger Rebbe’s Shu”t Divrei Yatziv (O.C. vol. 2:230; maintaining that those who are makpid on Zman Rabbeinu Tam for Tzeis Hakochavim should keep the same for fasting, and certainly not break fasts before 60 minutes after Shkiya).
See Rav Yitzchak Yaakov Fuchs’ (author of Halichos Bas Yisrael and other sefarim) recent Taanis Asarah B’Teves 5781 B’Erev Shabbos Kodesh, based on the Mishnah Berurah’s comments (271:1 and Shaar Hatziyun 639:67).
See the Selicha for Asarah B’Teves that starts with the word Ezkerah, generally attributed to Rav Yosef Tov-Alem (Bonfils). As pointed out by Rabbi Moshe Boruch Kaufman, at the end of said Selicha, it seems to include a fourth tragedy worth fasting for – the tzara of Bavel first hearing the news of the Churban Beis Hamikdash on the 5th of Teves. This ‘Yom Hashamua’ is mentioned in Gemara Rosh Hashana (18b) and Yerushalmi Taanis (Ch. 4, Halacha 5). See Rabbi Yitzchok Weinberg’s recent excellent Lechem Yomayam (on Chodshei Kislev and Teves, Chodesh Teves 2) at length as to why this shittah of Rabbi Shimon’s, to fast on the 5th of Teves, is not the practical halacha.
Tur,Beis Yosef, and Shulchan Aruch (O.C. 580).
Tur and Shulchan Aruch (O.C. 549 and 550).
As told at length in Gemara Megillah 9a. For a slightly different version see Maseches Sofrim (Ch. 1:7-8). This quote is found in Megillas Taanis (Ch. 13), and cited by the Tur and Shulchan Aruch (Orach Chaim 580). See Sefer HaToda’ah (vol. 1, Ch. 8, Chodesh Teves, par. Yom Kasheh) at length.
See Tur and Shulchan Aruch (Orach Chaim 580; quoting theBeHa”G, Hilchos Tisha B’Av V’Taanis 18), “lo noda bo eizo hi hatzara she’eera bo.” This quote is essentially originally found in Megillas Taanis (ibid.). However, many poskim, including the Ba’er HaGolah (ad loc. 4), Magen Avraham (ad loc. 6), Taz (ad loc. 1; who concludes “tzarich iyun rav” on the Tur and Shulchan Aruch for not knowing that Ezra HaSofer died on that day), Elyah Rabba (ad loc. 5), Rav Yaakov Emden (Siddur Amudei Shamayim vol. 2 pg. 149b), Pri Megadim (ad loc. Mishbetzos Zahav 1), Ba’er Heitiv (ad loc. 6), Mishnah Berurah (ad loc. 13), and Kaf Hachaim (ad loc. 20), all cite the Kol Bo (63), BeHa”G (ibid.), or the Selichos of Asarah B’Teves (ibid.) that the tzara on that day is that Ezra HaSofer died. The Aruch Hashulchan (ad loc. 3) diplomatically states that originally they did not know which tragedy occurred on that day to mandate fasting, and afterwards it was revealed that it was due to Ezra HaSofer’s passing on that day. [Interestingly, the Kaf Hachaim (ibid.) cites the Shulchan Gavoah (ad loc. 3) and others who maintain that Ezra really passed away on Asarah B’Teves. But, since it was already a scheduled fast day due to Nevuchadnetzar’s siege, its observance of fasting due to Ezra’s passing was pushed to the ninth of Teves.] Rav Yonason Eibeschutz (Ya’aros Dvash vol. 2:192-193) gives an interesting variation on this theme. He maintains that since Ezra’s role in Klal Yisrael in his time was akin to Moshe Rabbeinu’s, Chazal wanted to withhold publication of the day of his passing, similar to the Torah stating that “no one knows of Moshe’s burial place” (Devarim, V’Zos HaBracha Ch. 34:6). However, the Chida (Birkei Yosef, Orach Chaim 580) points out that the statement in Megillas Taanis (and later cited by the BeHa”G) that “lo kasvu Rabboseinu al mah hu” seem to be referring to a separate occurrence than its next listing, that Ezra HaSofer died on that day, and that they are not exclusively one and the same. The Chasam Sofer (Toras Moshe, Parshas Vayigash, Drush for 8 Teves s.v. kasav BeHa”G) answers that Ezra was similar to Moshe Rabbeinu, and drastically improved the spiritual state of the Jewish people, and yet, even after he died, Klal Yisrael felt satisfied and blessed simply to have been led by him when he was alive, and did not see any reason to fast on the day he died. Yet, when the Torah was later translated into Greek, enabling the “Tzaraas of the Minim”, only then did they realize the import of Ezra’s passing and established it as a fast day (similar to Moshe Rabbeinu’s passing on the 7th of Adar also being on the list of proper days to fast in Tur and Shulchan Aruch, O.C. 580: end 2). Yet, previously, they did not know why to fast on the 9th of Teves.
As found throughout Shas - see for example Bava Kama (82a) and Kesuvos (3a).
This follows the consensus that the last of the Neviim, Malachi, was none other than Ezra HaSofer. See Gemara Megillah (15a), Targum Yonason on Malachi (Ch. 1:1), and Tosafos (Yevamos 86b end s.v. mipnei). It is also implied in Gemara Zevachim (62a) and Sanhedrin (21b), regarding who established the Torah’s script as ‘Ashuris.’ Thanks are due to Rabbi Reuven Chaim Klein for pointing out several of these sources.
Rav Baruch Teumim-Frankel (author of the Imrei Baruch, in his glosses to Shulchan Aruch O.C. 580) cites several other sources opining different tzaddikim’s passings on the 9th of Teves as the reason for fasting, including the enigmatic Shimon HaKalphus, “who saved Klal Yisrael during the days of the Pritzim,” and to whom ‘Nishmas’ and ‘Etein Tehilla,’ a Piyut that is part of Yom Kippur liturgy, is attributed (see the Haggadah Marbeh Lesaper of Rav Yedidyah Weil, son of the Korban Nesanel, pg. 114; and Seder Avodas Yisrael, pg. 206, in the commentary to ‘Nishmas’). This reason is also cited by Rav Aharon Wirmush, renownedtalmid of the Shaagas Aryeh, in his Me’orei Ohr (vol. 4, pg. 110b, on Taanis; this volume is also called Od L’Moed), citing a ‘Sefer Zichronos’ that he once saw. Known as Patrus, it has been surmised that Shimon HaKalphus was a Jewish pope, placed by Chazal to infiltrate the early Christians, to ensure that Christianity became a separate religion (see Otzar Midrashim [Eisenstein] vol. 2, pg. 557-558 and the Oz VeHadar edition of Gemara Avodah Zarah 10a, Haghos U’Tziyunim 30; citing an original manuscript of Rashi’s that had been censored for hundreds of years). Some opine that he was ‘Ben Patora’ mentioned in Gemara Bava Metzia (62b). Although we do find Shimon HaKalphus (or Kippa) mentioned derisively as ‘Shimon Petter Chamor’ by several Rishonim, including the Machzor Vitry (Pesach 66), and Rav Yehuda HaChassid (Sefer Chassidim 193), on the other hand and quite interestingly, while referencing the laws of the Yomim Noraim (325) the Machzor Vitry himself refers to Shimon Kippa quite approvingly, if not downright reverently. In the footnotes of the Berlin edition of the Machzor Vitry (from 1893; pg. 362, footnote 5) the editor, Rav Shimon HaLevi Ish Horowitz, posits that this is not actually an outright contradiction in the Machzor Vitry, but rather a machlokes between his mentors, Rashi and Rabbeinu Tam. He postulates that the first mention in the Machzor Vitry, that “Shimon Petter Chamor was certainly not the composer of ‘Nishmas,’ and all who claim such will have to bring a Korban Chatas Shmeinah when the Beis HaMikdash will be rebuilt,” was from a handwritten manuscript of Rashi’s. Conversely, the second mention, that “Shimon Kippa was the one who set the order of the Yom Kippur tefillos and composed ‘Etein Tehilla,” was the opinion of Rabbeinu Tam (whom the Machzor Vitry quoted as the source of the ruling of that paragraph about allowing Piyutim and personal additions during Shemoneh Esrei), who held that Shimon Kippa’s kavanna in all that he did was exclusively Lesheim Shamayim. The Sefer Chassidim (ibid.) takes an alternate approach, explaining that even though Shimon Kippa was indeed a tzaddik, nevertheless since he was technically a meshumad, and people followed in his ways, he was called a derogatory nickname, ‘Shimon Petter Chamor,’ as is the proper custom to do with meshumadim, as fulfillment of the pasuk in Tehillim (Ch. 116:8) “Kimohem Yihiyu Oseihem.” On the other hand, it must be noted that this description was not accepted by all. In fact, even the controversial Italian scholar R’ Shmuel Dovid Luzzato (Shada”l), in his Mevo L’Machzor K’Minhag Bnei Roma (published 1856; pg. 7) wrote that he pondered and wondered about Rabbeinu Tam’s words for over twenty years, until he realized that Rabbeinu Tam must have believed in the “shamuos shav,” ‘false rumors,’ about the founding of Christianity, that were spread, albeit with good intention, during the years of persecution and forced conversions, “k’kavana tova l’chazek emunas hahamon.”
The second tzaddik’s passing on that day that Rav Teumim-Frankel cites was Rav Yosef HaLevi, son of Rav Shmuel HaNaggid, who was assassinated on the 9th of Teves in 1066, thus ending the Golden Age for Jewry in Spain. He quotes the Raavad’s Sefer HaKabbalah that “when Rabboseinu HaKadmonim wrote Megillas Taanis and established a fast on the 9th of Teves, they themselves didn’t know the reason. Later on, after Rav Yosef HaNaggid was assassinated we knew that they foresaw this tragedy with Ruach HaKodesh.” An additional reason for fasting on this day is cited by the Rema in his commentary to Megillas Esther (Mechir Yayin, Ch. 2:16) that we fast on the 9th of Teves as Esther was forcibly taken to Achashveirosh’s palace in the month of Teves (possibly on this day). Interestingly, some posit, as heard in the name of Rav Moshe Shapiro; also found in the Davar B’Ito calendar (9 Teves) and in Netei Gavriel (Hilchos Chanuka, Inyanei Nittel, pg. 416; quoting the Tosafos Chadashim on Megillas Taanis; also referred to as the ‘Mefareish’ of the Vilna Edition of Megillas Taanis), that the real reason for fasting is that the 9th of Teves is the true birthday of ‘Oso HaIsh’, in whose name myriads of Jews over the millennia were R”l murdered. The origin of this claim seems to be the 12th century Sefer HaIbur by Rav Avraham bar Chiya (pg. 109). In fact, the Netei Gavriel (ibid.) cites that some say that Nittel, the name used for the Christian December holiday, actually stands for Nolad Y eishu T es L’Teves. The author wishes to thank R’ Yitzchak Goodman, as well as Rabbi Dr. Eliezer Brodt, for pointing out several of these invaluable sources.
Sefer HaToda’ah (vol. 1, Ch. 8, Chodesh Teves, end par. Yom Kasheh).
Abudraham (Hilchos Taanis), cited with skepticism by the Beis Yosef (O.C. 550).
According to our calendar Asarah B’Teves cannot fall out on Shabbos. The Abudraham (ibid.) himself mentions this, as does the Magen Avraham (O.C. 550:4 and 5), Ba’er Heitiv (ad loc. 3), Aruch Hashulchan (ad loc. 2), and Mishnah Berurah (ad loc. 8). Everyone can easily make this calculation themselves. See Tur and Shulchan Aruch (O.C. 128:2) regarding which days various Roshei Chodesh can fall out on. For the month of Teves, Rosh Chodesh cannot fall out on a Thursday. That means Asarah B’Teves, ten days later, cannot fall out on Shabbos!
See Mishnah and Gemara (Megillah 5a), Rashi (ad loc. s.v. aval), Rambam (Hilchos Taaniyos Ch. 5:5), Tur and Shulchan Aruch (O.C. 550:3 and 552:10). This was discussed in a previous footnote. Rav Asher Weiss (in his Kuntress Shavu’i, Parshas Vayechi 5778, Year 17, vol. 12, : ‘Tzom Asarah B’Teves V’Shaar Tzomos Shechalu B’Shabbos, 3’) offers a novel approach as a solution to this conundrum. He opines that perhaps the Abudraham’s intent was not that the fast of Asarah B’Teves would push off Shabbos, but rather that as only regarding this fast it is stated “B’Etzem HaYom HaZeh,” perhaps he meant that it wouldn’t be merely pushed off until after Shabbos, but rather it would not be observed that year at all. Meaning, it is possible that the Abudraham was simply asserting that there would be no reason to fast for Asarah B’Teves if it would not be observed on that actual day. So, if Shabbos would push it off, it would get pushed off in its entirety until the next year. However, Rav Weiss concludes that this approach is indeed a chiddush and concedes that none of the Acharonim seem to learn this way, bein lehakel bein lehachmir.
 BeisYosef (O.C. end 550). Rashi (Megillah 5a s.v aval) and the Rambam (Hilchos Taaniyos Ch. 5:5) both explicitly rule that if Asarah B’Teves falls out on Shabbos then it gets pushed off. Other Rishonim who write this way include the Meiri (Megillah ad loc. and Taanis 30b), Kol Bo (end Hilchos Tisha B’Av), and Maharil (Hilchos Shiva Assar B’Tamuz), that if any of the Arba HaTzomos fall out on Shabbos they get pushed off until after Shabbos. Similarly, the Ibn Ezra, in his famous Shabbos Zemer ‘Ki Eshmera Shabbos’ explicitly states that Yom Kippur is the only fast that can override Shabbos(although admittedly, he may have just been referring to the metzius – that in our set calendar, it is the only one that can actually fall out on Shabbos – and hence trump its observance). This is how the Tur and Shulchan Aruch (O.C. 550:3), as well as later poskim rule as well. See for example, Shu”t Shoel U’Meishiv (Mahadura Kama vol. 3:179), Shu”t Maharam Brisk (vol. 3:99), and Aruch Hashulchan (O.C. 549: end 2).
 However, there are many who do defend the Abudraham’s statement based on the verse “B’Etzem HaYom HaZeh.” See for example Tikkun Yissachar (pg. 28a, Teves s.v. v’ode; interestingly citing this ruling as precedent from ‘Teshuvos HaGaonim,’ and not mentioning the Abudraham by name; although this might be a form of honorific) who actually rules that way. In fact, there is even a minority opinion (see Toras Chaim on Shulchan Aruch O.C. 550:4) who is choshesh for the Abudraham’s shittah lemaaseh and extends it, holding that one should not treat Asarah B’Teves as a minor fast, but rather observe it with similar restrictions as the major fasts: meaning keeping the five inuyim, akin to Yom Kippur. The Minchas Chinuch (Parshas Emor, Mitzva 301:7), explaining why nowadays we do not observe fast days for two days (as opposed to other Yomim Tovim, due to the safek yom), writes that the Neviim established fast days in specific months, but did not set the actual day it must be observed, hence the ambiguity in the Gemara on which days to observe them. Since they were never established as being mandated on one specific day, they are unaffected by the safek yom, and nowadays only one day must be observed. [A similar assessment regarding the establishment of fast days was actually expressed by several Rishonim, including the Ritva (Rosh Hashana 18b s.v. v’ha) and Tashbatz (Shu”t vol. 2:271).] The Minchas Chinuch adds that since both of these seemingly conflictory observances - the fasts for the destructions of the Batei Hamikdash, as well as the Mitzvah of Oneg Shabbos - are essentially Divrei Kabbalah (meaning, instituted in the times of the Neviim), why shouldn’t such a fast day be able to trump Oneg Shabbos? Especially one that was established as “B’Etzem HaYom HaZeh.” Rav Chaim Soloveitchik of Brisk (ChiddusheiHaGra”ch V’HaGri”z al Shas, ‘Stencils,’ pg. 27:44) takes this idea a step further to explain the Abudraham’s statement (although quite curiously, he inexplicably credits the BeHa”G with this statement, who in fact makes no mention of this; and does not mention the Abudraham; quite possibly a typo). He asserts that Asarah B’Teves is the exception to this rule of the Neviim’s ambiguity of exact day, since it is stated about it that it must be observed “B’Etzem HaYom HaZeh,” and therefore would be fasted upon even if it fell on Shabbos. Similarly, the Ohr Somayach (Hilchos Taaniyos Ch. 5:6 s.v. v’hinei, in the brackets) defends the Abudraham’s statement, based on a diyuk in the Gemara’s (Eruvin ibid.) choice of question about whether we complete a Taanis Yachid on Friday, with no mention of a Taanis Tzibur. He posits that the reason the Gemara did not cite such a case, is that Asarah B’Teves is the only Taanis Tzibur that can fall out on Friday, and if it can override Shabbos due to “B’Etzem HaYom HaZeh,” then certainly one would be required to fast the whole Friday for it! Hence, there was no reason for the Gemara to ask it. In other words, the Gemara’s question only starts if the fast would be pushed off if it fell on Shabbos, as then we are uncertain what the din would be regarding completing it if it fell out on Friday. As the Gemara only asked germane to a Taanis Yachid, this implies that regarding a Taanis Tzibbur the fast would triumph. Moreover, the Ohr Somayach posits that perhaps the fact that we complete the fast, fasting into Shabbos when Asarah B’Teves occurs on Erev Shabbos, would help prove that if it fell out on Shabbos, we would do the same - as it is possible that it is only problematic to observe a full 24-hour fast on Shabbos. But, as Asarah B’Teves is only a daytime fast, perhaps it is not conflictory with proper Shabbos observance. On the other hand, the Torah Temimah, in his Tosefes Bracha (Parshas Emor, pg. 211-212; thanks are due to Rabbi Herbert Russ for pointing out this invaluable source) argues that “B’Etzem HaYom HaZeh” should not prove a Shabbos fast, as when the pasuk says the same regarding Yom Kippur (Parashas Emor, Vayikra Ch. 23:29), it is a command that we must afflict ourselves on that exact day. That is why we fast on Yom Kippur that falls out on Shabbos. Yet, when referring to Asarah B’Teves, Yechezkel HaNavi was simply detailing when the siege actually started: that it was on that day, in the middle of the day; similar to the wording used to describe the animals entering Noach’s Teiva and Avrohom Avinu’s Bris Milah; with no connection to the fast that was later declared to commemorate this tragic incident. Accordingly, he avers that we would not fast if Asarah B’Teves would fall out on Shabbos. For more on this fascinating topic, as well as varying approaches, see Rav Avrohom Gurwicz’s Ohr Avrohom (Ch. 5, page 164 and on) and Rav Asher Weiss’s Minchas Asher (Moadim vol. 2, Tzomos 43).
Ya’aros Dvash (Vol. 1, Drush 2 for 9 Teves, 32-33; see also vol. 2:191-193 s.v. v’hinei yadua), Bnei Yissaschar (Maamrei Chodesh Kislev/Teves 14:1), and Shu”t Shoel U’Meishiv (Mahadura Kama vol. 3:179); see also Shu”t Maharam Brisk (vol. 3:99). The Chasam Sofer (Toras Moshe, Parshas Vayigash pg. 40b s.v. vad”z) also cites this reason and explains that it is only at the end of a tragedy when salvation has a chance to sprout. We see this from the famous Gemara at the end of Makkos (24a-b) with Rabbi Akiva, who laughed when he saw foxes wandering through the ruins of the Beis HaMikdash. Only when a tragedy is complete can there be a glimmer of hope for the future redemption. See also sefer Siach Yitzchak (pg. 293) and R’ Moshe Chaim Leitner’s sefer Tzom Ha’Asiri at length. Rav Yonason Eibeschutz adds that according to his calculations, Nevuchadnetzar’s actual siege on that first Asarah B’Teves commenced on Shabbos; meaning that that Asarah B’Teves that Yechezkel wrote “B’Etzem HaYom HaZeh” about was actually Shabbos. The Chasam Sofer (Toras Moshe, Parshas Vayechi, Drush for 8 Teves 5599, s.v. ksiv) agrees with this assessment and offers a variation, that the reason Nevuchadnetzar was successful in his conquest of Yerushalayim, as opposed to Sancheirev, was due to lack of Shemiras Shabbos among its inhabitants!
Midrash Tanchuma (Tazria 9). However, in Parshas Bereishis, the Midrash Tanchuma (ad loc. 2 and 3), actually takes a very strong stance against fasting on Shabbos, as “Kavod Shabbos is adif than one thousand fasts”!
Toras Moshe (vol. 2, Parshas Vayikra, Drush for 7 Adar, pp. 9b-10a, s.v. kasuv).
Yerushalmi Yoma (Ch. 1, Halacha 1, 6a).
Rambam (Hilchos Taaniyos Ch. 5:1); see also Mishnah Berurah (549:1).
Zecharia (Ch. 8:19), as per the understanding of Rabbi Akiva (Rosh Hashana 18b). See also Knesses HaGedolah (O.C. 550, He’aros on Beis Yosef) for a fascinating hesber.
Disclaimer: This is not a comprehensive guide, rather a brief summary to raise awareness of the issues. In any real case one should ask a competent Halachic authority.
L'iluy Nishmas the Rosh HaYeshiva - Rav Chonoh Menachem Mendel ben R' Yechezkel Shraga, Rav Yaakov Yeshaya ben R' Boruch Yehuda, and l'zchus for Shira Yaffa bas Rochel Miriam and her children for a yeshua teikef u'miyad!