All Jews fast on the four fast days mentioned by the prophets which are: Tzom Gedalya (the third of Tishrei), Asara B'Tevet (tenth of Tevet), Shiva Asar BeTamuz (seventeenth of Tamuz), and Tisha BeAv (ninth of Av).  The significance and background of these fasts are explained below. The first three are discussed in this article. For the other fasts please see the following links: Tisha BeAv, Tanit Ester, and Tanit Bechorim. Another related page is Commemoration of the Destruction of the Temple (Zecher LeChurban). The principle purpose of the fast days is to cause one to reflect upon one's ways in order to repent.
- 1 Tzom Gedalya
- 2 Asara B'Tevet
- 3 Shiva Asar BeTamuz
- 4 Taanit Esther
- 5 Communal Fast days
- 5.1 Who Fasts
- 5.2 When does the fast start?
- 5.3 When does the Fast end?
- 5.4 Travel
- 5.5 Washing oneself and swimming
- 5.6 Brushing One’s Teeth
- 5.7 Prayer
- 6 Other Halachas of Fast Days
- 7 Individual Fast Days
- 8 Related Pages
- 9 Links
- 10 Sources
- Tzom Gedalya is observed on the 3rd of Tishri. 
- Tzom Gedalya commemorates the death of Gedalya Ben Achikam and the extinguishing of the spark of Yisrael causing the exile. 
- Asara B'Tevet commemorates the tragedy of Nevuchadnezzar laying siege to Yerushalayim. 
On a Friday
- Asara B'Tevet is the only fast that can fall out on a Friday. 
- Even if Asara B'Tevet falls out on a Friday one should fast until tzet hakovachim even though the fast would carry into shabbat. 
- It is permitted to recite Kabbalat Shabbat and Arvit earlier than usual so that people can begin kiddush at home at tzet hakochavim. 
- All the normal Shabbat preparations such as showering and shaving should be done normally, even for those who normally wouldn't shave or shower on a fast because of the kavod shabbat obligation. 
- If Asara B'Tevet falls out on friday, shacharit is prayed as usual. For Mincha, the torah and haftara are read, aneinu is recited during the amida. Tachanun and avinu malkenu are not said. 
- One should try to say mincha earlier on Asara B'Tevet that falls out on a Friday. 
- Those who wear tefillin during mincha on a fast day, should recite mincha early on Friday so as not to have his tefillin on too close to Shabbat 
- If Asara B'Tevet falls out to be on Friday one may taste the food if one spits it out and doesn’t swallow. 
Shiva Asar BeTamuz
- Shiva Asar BeTamuz commemorates 5 things: 1) The Luchot were broken. 2) The Korban Tamid in the 1st Bet Hamikdash was abolished. 3) In the 2nd Bet Hamikdash destruction, the city of Jerusalem was breached. 4) The Torah was burned by Apostomus. 5) An idol was put in the Bet Hamikdash. 
- The fast of Shiva Asar BeTamuz is observed on the seventeenth of Tamuz and not the ninth of Tamuz. 
see Tanit Ester page
Communal Fast days
- The 3 minor fast day of Tzom Gedalya, Asara B'Tevet, and Shiva Asar B'Tamuz all mourn different aspects of the destruction of the Beit HaMikdash. There is a dispute whether nowadays these fasts are considered a binding communal practice or derived from the words of prophets.
- Everybody is obligated to fasts on these public fast days. 
- Even rabbis or teachers whose fasting may cause their learning to be of lower quality should fast on these fast days including Taanit Esther. 
- Anyone who isn't fasting for whatever reason should try to eat in private. 
- Anybody who doesn't fast because they are exempt does not need a hatarat nedarim, but if it isn't too hard to do one, then praiseworthy is somebody who does. 
Pregnant or Nursing Women
- A pregnant woman need not fast on these fasts except for Tisha BeAv.  According to Ashkenazim, this is only true if the pregnant woman is having pain or they are weak, however, according to Sephardim, this is true even if the woman isn't in pain.Nonetheless, if the woman isn't fasting she shouldn't eat to enjoyment but rather only what is necessary. 
- A nursing woman is exempt from fasting on the fasts except for Tisha BeAv. Some say this includes a women who has finished nursing as long as she is within 2 years of the birth, and some say this only includes somebody who is actually nursing the baby. 
- A pregnant or nursing woman who does not need to fast, does not need to make up the fast on a different day. 
- One who is sick, even if there is no danger of dying is exempt from fasting and shouldn't fast. 
- Old, sick people who suffer a lot from fasting are exempt from these fasts, including Tisha BeAv. 
- If one is sick and does not fast he need not make up his fast on a different day. 
- One need not train his children to fast, even at the age of 12 for boys or eleven for girls.  Although many boys have the custom to fast three fasts before they become bar-mitzvah, but this custom has no source. 
- A groom within the seven days of his wedding, the father of a baby boy, a sandak, a mohel must fast on these four fasts unless the fast was postponed because it originally fell out on shabbat, in which case they are all exempt from all these fasts and should eat after mid-day. 
When does the fast start?
- Communal fasts which do not start at night only begin at Olot HaShachar. 
- If one went to sleep at night and wakes up before Olot HaShachar one may not eat unless one stipulated before going to sleep that one didn’t begin the fast and one would eat and drink before Olot HaShachar.  However, the Zohar is strict even such a case and one should only be lenient regarding drinks or if it's difficult to fast without eating before Olot HaShachar.  If one didn't make a stipulation before going to sleep and one woke up before Olot HaShachar, one is permitted to drink before Olot HaShachar. 
Eating Before the Fast
- Some poskim say that one should avoid eating too much before a fast, as this may make him feel the fasting less. 
When does the Fast end?
- Any fast which one didn’t complete until Tzet HaKochavim is considered as though one didn't fast. 
- Some poskim allow somebody who ends Shabbat according to the time of Rabbeinu Tam, to be lenient and end these rabbinic fasts according to the time of the Gra,  while other say he should wait 
- Some poskim says that one who travels during a fast, should finish the fast according to his arrival destination, whether this makes it longer or shorter. 
Washing oneself and swimming
- A Baal Nefesh should be strict not to wash oneself in hot water or anoint oneself, however it’s permitted to wash with cold water or wash one’s hands, feet, and face with hot water. 
- One shouldn’t go swimming in a pool or ocean on a fast day.  One is permitted to swim the night before a fast. 
Brushing One’s Teeth
- According to Ashkenazim, one shouldn't brush one's teeth on a fast day unless one will be in pain by not brushing, such as someone who brushes daily. Since Tisha B'Av is more severe, one shouldn't brush one's teeth on Tisha B'Av unless not brushing will cause oneself major pain. According to Sephardim, those who regularly brush their teeth with toothbrush and toothpaste may brush on a fast day with less than a Revi'it of water but they should bend over while rinsing so as not to swallow the water. 
- According to Ashkenazim, only if one is in pain may one rinse one’s mouth and in such a case one should bend one’s head downward so one doesn’t swallow any water. On Tisha BeAv one may rinse one’s mouth only if one is in great pain, and on Yom Kippur one must be strict. According to Sephardim, for all fasts besides Tisha BeAv and Yom Kippur, in a case of need one may rinse one’s mouth with less than a Revi'it of water as long as one is careful to spit it out completely. 
- One may swallow saliva that accumulates in one’s mouth.  Some say that if it’s easy one should be strict and spit it out.  While others say that the minhag is to be lenient altogether. 
- A kohen who is not fasting, should not go up for birkat kohanim during mincha. 
- If mincha went past sunset, birkat kohanim may still be recited within thirteen and a half minutes but not after that. 
Tefillin in Mincha
- Some Sephardim had the minhag to wear tefillin on fast days at Mincha so as to complete 100 Brachot, however this minhag isn’t very widespread. 
- Many have the custom to recite Avinu Malkeinu on public fast days. One can even say Avinu Malkeinu when davening without a minyan. 
Recitation of Aneinu
- The addition of aneinu is recited by the sephardim during Shacharit and Mincha  , and for the ashkenazim only in mincha. 
- One who isn't fasting doesn't recite aneinu.  A child who is not fasting still recites aneinu for chinuch purposes. 
- The individual inserts this paragraph in the beracha of shomea tefilla, and finishes as usual, and the chazzan during chazarat hashatz says it as a beracha on its own between the berachot of goel and rofe. 
- If one forgot to recite aneinu, and already said baruch atta Hashem to conclude the beracha of shomea tefilla, he shouldn't say lamdeini chukecha there or insert it right after the beracha, but instead should say it after elokai nitzor and yihyu liratzon and say it without any beracha. 
- If someone is reciting his silent shmoneh esrei along with the chazzan's chazzarat hashatz, he should say aneinu in shomea tefilla, and not with the chazzan saying it between goel and rofe. 
- For these four fasts, the beracha of aneinu is recited during chazarat hashatz as a beracha on its own as long as there are six or more fasting.  These 6 all have to be people who haven't prayed yet. 
- If one forgot to say Aneinu in "Shomea Tefila" one should recite it in "Elokai Netzor." 
- If the shaliach tzibur forgot to say Aneinu in the Chazarat Hashatz he should recite it in "Shomea Tefila." 
- One shouldn't skip Aneinu in Shemona Esrei to say it after Shemona Esrei so that one can answer kedusha.
Reading the Torah
- On all rabbinic public fast days, we read Shemot 32:11-14 and 34:1-10, both in the morning and the afternoon, except Tisha B'Av morning. 
- According to Ashkenazim, on the fasts other than Tisha B'av the Haftara of Isaiah 55:6-56:8 is read during mincha but not shacharit.  If a Sephardi is asked to go up he should try and refuse, unless he has already been called by name, in which case he should go up and say the berachot. 
- Ashkenazim have a custom is certain verses are read aloud by the congregation. The individual who is called up for that aliyah should not read the verses aloud with the congregation but instead should wait until the reader says them aloud and read along with him. 
- On a weekday other than a Monday and Thursday, somebody who is not fasting may not receive an aliya to the torah.  On a Monday or Thursday at Shacharit, since there is torah reading anyway, some poskim permit it. 
- The torah can be read even if there are only six men fasting. 
Other Halachas of Fast Days
- On all of these rabbinic fasts besides for tisha b'av one is permitted to wash, anoint, wear leather, and have relations. 
- On the day of a Taanis one should refrain from unnecessarily touching foods, lest one inadvertently eat during the fast. 
- One should be careful to control his anger on a fast day. 
- On the Shabbat prior to Asara B'Tevet and Shiva Asar bitammuz, we announce the day of the fast prior to saying Mussaf. 
- A restaurant or store owner should preferably refrain from giving out food unless it is known that it is for sick people or for after the fast, and even if there are other places where people can access food. 
- Prescribed medications may be taken if it doesn't have a taste. If one has difficulty swallowing the pills, and a person is taking the pills because of a sickness for which the doctor prescribed these pills, it is permitted to swallow the pills with a minimal amount of water, the amount needed to swallow them, even on Tisha B'av. 
- Some poskim permit taking caffeine suppositories during the fast, to avoid caffeine related headaches. 
If one made a Bracha by Accident
- According to Sephardim, if one made a Bracha by accident and then realized that it was a fast day, one should eat a very small amount just enough that one can taste it and continue on fasting. According to Ashkenazim, one shouldn't taste anything but just say Baruch Shem. 
If one ate or drank inadvertently
- If one ate by mistake on a fast day he should nevertheless continue fasting afterwards. 
- It is prohibited to chew gum on a fast day, unless the gum has no taste whatsoever. 
- It’s permissible to smoke on a fast day except on Tisha BeAv (disregarding whether it’s permissible to smoke because of the health issue). 
- According to Sephardim, on a fast day besides Tisha BeAv and Yom Kippur one may taste food (to see if it’s spiced) up to a Revi'it as long as one spits it out afterwards. According to Ashkenazim, one may not taste food on any communal fast day except where one needs to taste a food for a Suedat Mitzvah to see if it’s spiced well. 
- Preferably one should be strict when making sure to have less than a Revi'it to consider this Revi'it to include anything one tasted the whole day, however, the strict law is that one only has to make sure to have less than a Revi'it each time one tastes. 
Tasting Food on Friday
- In general, it’s a mitzvah to taste the Shabbat food before Shabbat to know if tastes right (Tasting food in preparation of Shabbat). However, on Friday of Shabbat Chazon, one shouldn’t taste the food. 
Making a Shehecheyanu
Taking a haircut
- There’s a dispute whether one may take a haircut on a fast day and it’s preferable not to. 
- It’s customary to give Tzedaka at Mincha on a fast day, the value of the amount of food one would have eaten that day. 
- The primary purpose of the Fast days is to inspire a person to do Teshuva and remember his sins and the sins of our fathers which caused the tragedy which is being commemorated to occur. Thus, a person should should make time on a fast day to think about one's actions and do Teshuva. Those people who take walks and do other activities which are a waste of time when they are fasting have missed a major point of the fast. Nonetheless, one may not exempt oneself with only doing Teshuva because fasting on these days is a Mitzvah MeDivrei HaNevim. 
Individual Fast Days
- It is possible for an individual to take upon themselves to fast for a day and it will serve for an atonement and merit. Fasting for the purpose of teshuva or receiving atonement is an important mitzvah.
- Nonetheless, a talmid chacham who is dedicated to learning shouldn't accept upon himself to fast because it'll cause him to learn less.  A teacher is like a talmid chacham for this purpose and may not fast individual fasts.
- If a person does fast an individual fast he may not publicize it to others in order to receive honor.
- If a person wants to fast he must accept it upon himself the day before. The minhag is to accept the fast day at mincha the day before.
Individual Partial Fast Days
- For an individual fast day, a person needs to fast until Tzet HaKochavim. 
- A fast of hours (Tanit Shaot) is only effective if a person didn't eat in the morning and then decided not to eat the rest of the day. In such a case he can recite Anenu at mincha. Some poskim hold that a fast of hours only is effective if one accepted to fast partially from the previous day. Either he can accept to fast in the morning and then if he changes his mind to complete the day or he can accept to fast in the afternoon and then if he changes his mind and ends up not eating in the morning that is a fast of hours for anenu.
- According to Ashkenazim it is possible to accept upon oneself to fast a partial fast and break it before the night. If someone accepted a partial fast he can break the fast after Plag Mincha and if he is weak he can break it after Mincha Gedola.
- The prophet Zechariyah (8:19) stated that in the future the fast of the fourth, fifth, seventh, and tenth will become days of happiness for the Jews. In Gemara Rosh Hashana 18b, Rabbi Akiva explains that number in the pasuk refers to the number of the month. Thus, the fast of fourth is the ninth of Tamuz, the fifth is the ninth of Av, the seventh is the third of Tishrei (fast of Gedalyah), and tenth is tenth of Tevet. The Tur 549:1 and Rambam (Taniot 5:4) rule like Rabbi Akiva. Tur 549:2 explains that on the ninth of Tamuz the wall of Yerushalyim was broken by the first Bet HaMikdash, however, nowadays we fast on the seventeenth of Tamuz when the wall of Yerushalyim was broken by the second Bet HaMikdash. These four fasts are codified as halacha by the Rambam (Taniot 5:2-3), S”A 549:1, Mishna Brurah 549:1, and Yalkut Yosef (Moadim pg 527).
- Rambam Hilchot Taaniyot 5:1
- Chazon Ovadia (Laws of the Four Fasts, Halacha 3), Shulchan Aruch 549:1, Rambam Taaniyot 5:2.
- Rambam (Taniyot 5:2), Chazon Ovadia (Laws of the Four Fasts, Halacha 3, Mishna Brurah 549:2, Kitzur Shulchan Aruch 121:2
- Rambam (Taniyot 5:2), Mishna Brurah 549:2, Kitzur Shulchan Aruch 121:3, Chazon Ovadia (Laws of the Four Fasts, Halacha 4)
- Magen Avraham 550:4, Aruch Hashulchan 550:2, Mishna Brura 550:10
- Shulchan Aruch 249:4, Yabea Omer 6:31. Aruch Hashulchan 549:2 quotes the Avudarham that even if Asara B'Tevet fell out on shabbat, which can no longer happen because of the way the calendar is set (Magen Vraham 550:4-5), we would have to fast. Chatam Sofer in his sefer torat moshe on the torah pg. 346 explains that this is similar to the concept of fasting for a bad dream (taanit chalom), that every year on Asara B'Tevet we are judged if we will merit to see the beit hamikdash rebuilt.
- Nitei Gavriel Chanuka 63:6: notes 9-10. In 63:7 he adds that some poskim are even more lenient with the time of tzet hakochavim than they usually are. Rama 249:4 quotes an opinion that if you pray early and finish Arvit before Tzet HaKochavim you should eat, but then says that nevertheless on a public fast one should fast until Tzet HaKochavim and on a private fast, eat after davening.
- Rabbi Ari Enkin, Mishna Brura 550:6 and Baer Heitev 550:2
- Mishna Brura 603:3, Aruch Hashulchan 550:2. see Aruch Hashulchan there about a custom that existed to omit torah reading. for a lengthier discussion see Asara B'Teves on Erev Shabbos by Rabbi Aryeh Lebowitz
- Minhagei Eretz Yisrael 27:28, Nitei Gavriel 62:3 says that it is not proper to pray mournful prayers while dressed in Shabbat clothing so one should prayer earlier. He adds in the name of the Dvar Yehoshua 3:63 it is also good to distance the mournful prayers as far as possible from the Shabbat.
- Nitei Gavriel Chanuka 62:4
- Shemirat Shabbat KeHilchata 42:61 based on Shulchan Aruch 567:1, Mishna Brurah 567:6, Kaf Hachaim 567:10
- Mishna Taanit 26b, Rambam Taaniyot 5:2, Shibbolei Haleket 263, Chayei Adam 133:4, Mishna Brurah 549:2, Kitzur Shulchan Aruch 121:4, Aruch Hashulchan 549:3, Chazon Ovadia (Laws of the Four Fasts, Halacha 1), Yalkut Yosef Moadim page 527, Halachos of the Three Weeks page 1.
- Tur 549:2 explains that on the ninth of Tamuz the wall of Yerushalyim was broken by the first Bet HaMikdash, however, nowadays we fast on the seventeenth of Tamuz which was when the wall of Yerushalyim was broken by the second Bet HaMikdash. This codified as halacha by the Rambam (Taniot 5:2-3), S”A 549:2, Mishna Brurah 549:1, and Yalkut Yosef (Moadim pg 527).
- The Gemara Rosh Hashana 18b states based on the pasuk in Zecharya that if there's no Beit HaMikdash and persecution then these are fast days, if there's a Beit HaMikdash then they're holidays, however, if there's no Beit HaMikdash and no persecution these are dependent on the will of the people. The Maggid Mishna (Taniyot 5:5) writes that today it is only a minhag and will remain an obligation until the third Beit HaMikdash is built. The Tosfot (Megilah 5b s.v. verachatz) seems to agree. Regarding the communal practice changing see the Rashba (Rosh Hashana 18b s.v. ein shemad) who seems to assume that this communal practice could potentially change. See further on the minhag page. On the other hand, the Ramban (Torat HaAdam, Shaar HaAvelut, Inyan Aveilut Yeshana) who writes that today it was accepted as a obligation and today there is persecution in at least a segment of Israel, so it is a obligatory because of the words of the Navi. Tur 550 seems to agree.
- Levush 550:1, Magen Avraham 550:1, and Mishna Brurah 550:1 hold that primarily the minor fasts today are obligatory as communal practices when there isn't persecution. It is noteworthy that the Aruch Hashulchan 549:5 writes that it is obligatory today from the words of the Navi.
- Rambam Hilchot Taanit 1:4, Shulchan Aruch 550:1, Chayei Adam 133:6, Yabia Omer 1:33, Mishna Brurah 550:1, Aruch Hashulchan 459:5, Kitzur Shulchan Aruch 121:11.
- Yabia Omer 2:28:7
- Matei Ephraim 602:22, Shaare Ephraim 1:10, Minchas Elazar 3:3, Teshuvot Vihanhagot 2:265, Minhag Yisroel Torah 550:page 31, Nitei Gavriel (Bein Hametzarim) 1:page 64:footnote 22.
- Yabia Omer 2:30: 5-8
- Rama 550:1, Shulchan Aruch 554:5, Pri Megadim Eishel Avraham 550:1, Aruch Hashulchan 550:3, Yechave Daat 1:35.
The gemara in Pesachim 54b says that pregnant women and nursing women are required to fast on Yom Kippur and Tisha B'Av, implying that they are not required to fast on the other fast days. Hagahot Maimoniot Taaniot 5:1 says that this is because the other fasts are optional in nature. Yechave Daat 1:35 says that this begins from the end of the first trimester whether she feels the pain or not, unless she is having pains earlier in which case her exemption would start earlier. Mishna Brurah 550:3 and Aruch Hashulchan 550:3 say that it starts 40 days into pregnancy unless she has an unusual amount of pain.
- Rama 550:1 writes that pregnant or nursing woman are exempt from the three fast days (except Tisha BeAv) only if they are in a lot of pain. Then he adds even if they're not in a lot of pain they're not obligated to fast but rather that is the minhag unless they are in pain. Mishna Brurah 550:5 writes that if the woman is weak she doesn't have to be strict to fast. Shulchan Aruch 554:5, however, seems to say that pregnant and nursing women are exempt whether or not they are in pain. Yalkut Yosef 550:9-10 rules that in general pregnant and nursing women are exempt from fasting on the three minor fasts besides for Tisha BeAv.
- Shulchan Aruch 554:5, Mishna Brurah 550:5
- In Yechave Daat 1:35, Rav Ovadia Yosef concludes that if the woman feels sick she may eat, but if she feels like she can fast, she should try to fast. Or litzion 3:25:7 disagrees and says in that case she would only be exempt within thirty days of giving birth. This is also the ruling of Eishel Avraham Butchatch 550:1
- Sh"t Yechave Daat 1:35
- Mishna Brurah 550:4, Yalkut Yosef Moadim page 531, Sh"t Yechave Daat 1:35, Aruch Hashulchan 550:6, Teshuvot Vihanhagot 4:123.
- Yalkut Yosef Moadim page 532
- Sh"t Yechave Daat 1:35 and Biur Halacha 550
- Mishna Brurah 550:5 and Beiur Halacha "hakol" Yalkut Yosef Dinei Chinuch Katan page 239 and Moadim page 530, Eliya Rabbah 550:7, Chanoch Lanaar 21:footnote 9, Halichot Shlomo Moadim 2:page 398:3. Mishna Brurah 550:5 based on Magen Avraham 550:2 and Chayei Adam 133:6 say that when children do not fast they should only eat the amount of food they need but Halichot Shlomo Moadim 2:page 398:footnote 10 says that this is not the custom.
- Halichot Shlomo Moadim 2:page 399:footnote 11.
- Yabia Omer 1:34:11, 5:40, Mishna Brura 559:35. Rav Ovadia Yosef writes in Yabia Omer 27:10 that this is true even of tzom gedalia, even though some rishonim say the tragedy occurred on Rosh Hashana it is not considered a postponed fast unless it actually fell out on Shabbat.
- Shulchan Aruch 564:1, Yalkut Yosef Moadim page 529, gemara taanit 12a.
- S”A 564:1 writes that if one doesn't go to sleep one may continue to eat until Olot HaSachar and if one went to sleep one may still eat if one made a stipulation that one will continue to eat after he wakes up before Olot HaShachar (according to the explanation of Mishna Brurah 564:4). This is based on the gemara taanit 12a which says that although the fast the fast begins at amud hashachar if one goes to sleep than the fast begins then. The Yerushalmi Taanit 1:4 allows for this stipulation before going to sleep that you intend to eat before amud hashachar. Rama 564:1 comments that one doesn't need to make a stipulation for drinks. However, Mishna Brurah 564:6 writes that the achronim say it's preferable to make a stipulation for both foods and drinks.
- Even though the Shulchan Aruch 564:1 makes no mention of the Zohar, the Mishna Brurah 564:28 and Yalkut Yosef (Tefilah, vol 1, pg 126, 89:43, and 550:3) quote the Zohar which is strict regarding eating after one slept before Olot HaShachar, however, the Zohar isn't strict about drinking. Yalkut Yosef adds that if it's difficult for one to fast if one doesn't eat before Olot HaShachar one may do so (after stipulating before going to sleep). See Sh”t Yabia Omer 5:22(5), Piskei Teshuvot 564:1 and 89:21.
- Mishna Brurah 564:6 as well as Kaf HaChaim 564:10 both say that if you for some reason did not make this stipulation before you went to sleep and you woke up before dawn thirsty you are permitted to drink. Shevet hakehasi 1:180 says that one who didn't know this halachah and ate in the morning without having made the stipulation the night before, may still recite aneinu.
- Eliya Rabbah 563:1, Kaf Hachayim 549:11
- S”A 562:1, Mordechai Taanis 631, Yalkut Yosef Moadim page 529. The Gemara in Taanit 12a says that to be considered a fast a person needs to wait until the sun completes to set. Rabbeinu Yona quoted by the Rosh Shabbat 2:23 says from this gemara that the fast concludes at sunset. However, the Rosh himself in Taanit 1:12 says that the gemara is referring to the completion of the setting of the sun, namely tzet kavochavim. This is the source of the Shulchan Aruch 562:1. Aruch Hashulchan 562:9 and the Gra 562:2 say that since there are some rishonim who follow Rabbeinu Yona anyone who is lenient and relies on them should not be rebuked for it. See Aruch Hashulchan there who thinks this is also the opinion of the Rambam.
- The Gemara Pesachim 54b implies that only Tisha B'Av is treated like Yom Kippur and it is forbidden to eat during Ben Hashemashot, however, it would be permitted to eat during the Ben Hashemashot. See the Avnei Nezer OC 429 for a fascinating explanation as to why that conclusion is correct. The Shaar HaTziyun 562:1 writes that even for the minor fast days we wait until the tzet hakochavim because we're concerned about the opinion of Rabbi Yose that Ben Hashemashot only begins after the Ben Hashemashot of Rabbi Yehuda ends. He notes from the Korban Netanel that we can't be lenient both to allow eating during Ben Hashemashot and also to follow the Ben Hashemashot of Rabbi Yehuda.
- Yalkut Yosef 293:4, Shearim Metzuyanim Bihalacha 123:4, Nitei Gavriel Bein Hamitzarim page 57
- Yisroel V’hazemanim 1:pages 573-578, Nitei Gavriel bein hamitzarim page 58.
- Iggerot Moshe 3:96, Rabbi Eli Mansour in the names of Rav Moshe and Chacham Ovadia Yosef, Vilechitcha Baderech page 59:1. This applies even if on Tisha BeAv his fast will last less than 24 hours. However, Sh"t Yaskil Avdi 8:38 says that although the public fast ends according to the time of his place of arrival, an individual has a personal obligation to fast twenty hours on Tisha BeAv and that he should continue fasting into the tenth of Av to complete his 24 hours.
- Mishna Brurah 550:6, Shaar HaTziyun 550:8, Kaf Hachayim 550:13. Yalkut Yosef Moadim page 530 permits washing one's body with hot water, but adds that one who is strict is praiseworthy. Aruch Hashulchan 550:3 also says that technically it is permitted to use hot water, but the custom has developed not to except on erev shabbat, but it is still permissible to use hot water.
- Mishna Brurah 550:6
- Piskei Teshuvot 550:6, Rivevot Ephraim 1:363:1 and 3:368, Sh”t Bear Moshe 3:77, Rav Moshe Feinstein quoted in Moadei Yeshurun page 108. Nitei Gavriel page 34 allows children to swim.
- Rav Moshe Feinstein quoted in Modanei Yeshurun 1:page 108
- Piskei Teshuvot 567:1 and Sh”t Minchat Yitzchak 4:109 hold that brushing teeth has the same status as rinsing one's teeth. Similarly, Rabbi Aryeh Lebowitz explained that someone who usually brushes and not brushing a whole day will cause one pain is allowed to brush on a minor fast day. Furthermore, based on Rav Schachter's opinion that all toothpaste is kosher since it isn't a food, Rabbi Lebowitz posits that one can certainly make the argument that brushing one's teeth is more lenient than rinsing one's mouth and is permitted on a fast day.
- Chazon Ovadyah (Arba Taniyot pg 28) rules that those who regularly brush their teeth with toothbrush and toothpaste may brush on a fast day with less than a Revi'it of water as long as they bend over while rinsing and spit it out afterwards. Rabbi Mansour on DailyHalacha.com agrees but adds that one shouldn't even gargle.
- Yalkut Yosef (Moadim pg 534) writes that for all fast days besides Tisha BeAv one if it will be difficult for one not to brush one is allowed to brush one's teeth as long as one doesn't put a Revi'it of water in one's mouth at a time and ensures that one doesn't swallow any water.
- Sh”t Minchat Yitzchak 4:109:2 rules that someone who has bad breath on Tisha BeAv may brush his teeth without water in order to pray with a clean mouth. Beer Moshe 8:94 agrees.
- S”A 567:3 writes that it’s improper to rinse one’s mouth on a fast day. Magen Avraham 567:6 writes that this is only according to the Rama who says not to taste food on any fast day, however, according to S”A who allows tasting on fast days besides for Tisha BeAv and Yom Kippur it is only improper if one rinses one’s mouth with more than a Reviyit. However, Kaf HaChaim 567:13 quotes the Nahar Shalom, Bigdei Yesha, and Maamer Mordechai who differentiate between tasting and rinsing and so Kaf HaChaim concludes that one shouldn’t rinse even with less than a Reviyit. Yet, Chazon Ovadyah (Arba Taniyot pg 27-8) rules like the Magen Avraham that for Sephardim in a case of need one may rinse one’s mouth with less than a Revi'it of water. Even though regarding brushing one’s teeth (pg 28) he adds that one should bend over according to the stringency of the Chaye Adam, regarding rinsing with less than a Revi'it it seems that one doesn’t have to bend over and such is the language of the summary (pg 515).
- Chaye Adam 132:20 writes that if one is in great pain one may rinse one’s mouth even on Tish BeAv if one is careful to bend one’s head downward so that one doesn’t come to swallow anything but one may not do so on Yom Kippur. Kaf Hachaim 567:14 quotes this. Mishna Brurah 567:11 differentiates saying that all fasts days one may rinse one’s mouth if one is in pain and by Tisha BeAv one may rinse one’s mouth only if one is in great pain and on Yom Kippur one must be strict. Sh”t Minchat Yitzchak 4:109(1) agrees with Mishna Brurah that for most fasts one may rinse if one is in pain and for Tisha BeAv one may only rinse if one is in great pain.
- Mishna Brurah 567:13
- Chaye Adam 132:22, Mateh Efraim 612:7, Moadim UZmanim 1:59
- Piskei Teshuvot 567:2, Bet Meir, Ashel Avraham, Aruch HaShulchan 567:4
- Yalkut Yosef Moadim page 551
- Yechave Daat 6:40
- Sh”t Yechave Daat 2:67. Rabbi Eli Mansour writes that this is in fact the minhag of the Syrians in Brooklyn. see Rabbi Maroof for two additional reasons for this custom
- Ishei Yisroel 45:45
- Shulchan Aruch 565:3 because even if you don't end up finishing the fast because you get sick from fasting, it is still a public fast day. Yalkut Yosef Moadim page 536 adds that one recites aneinu at night on tisha b’av.
- Mishna Brurah 557:3, Rama 565:3. Mishna Brurah 568:10 says that you should even say aneinu if you daven Mincha gedola because even if you end up eating you at least fasted until chatzot.
- Shevet Halevi 5:60:4:page 61, Halichot Shlomo Moadim 2:page 402:footnote 25.
- Shevet halevi 8:131
- Yalkut Yosef Moadim page 536-537 based on Shulchan Aruch 566:1
- Yabia Omer 1:22, Chayei Adam 24:18, Kitzur Shulchan Aruch 19:14, Aruch Hashulchan 565:3, Kaf Hachayim 119:28
- Yalkut Yosef Moadim page 537, Yabia Omer 2:34:6,Beiur Halacha 565:1
- Yalkut Yosef Moadim page 539, Yechave Daat 1:79. He adds that for Taanit Esther it is preferable to get 10 people fasting but if not, the beracha should still be recited.
- Yalkut Yosef page 542
- Kitzur Shulchan Aruch of Rav Rephael Baruch Toledano, Volume 1, Page 106
- Kitzur Shulchan Aruch of Rav Rephael Baruch Toledano, Volume 1, Page 106
- Chesed Lalafim 109 writes that one shouldn't skip aneinu in shemona esrei in order to catch answering kedusha with the congregation. Yabia Omer OC 2:34 and 9:66 discusses this topic at great length and agrees with the Chesed Lalafim. See the explanation of this on the Al Hanissim page regarding skipping Al Hanissim.
- Shulchan Aruch 566:1, Yalkut Yosef Moadim page 545.
- Rama 566:1. The basis for the haftorah at mincha on a fast day is from the gemara Tanit 12b discussing a fast for a drought and codified by the Rambam Taniyot 1:17. However, the Masechet Sofrim 17:5 writes that there were different minhagim whether or not to say a haftorah of Dirshu Hashem at mincha on a fast day or no haftorah. Bet Yosef 575:2 points out that the Rambam Tefillah 13:18 implies that there is no haftorah for a fast day besides for Tisha B'av or a fast for a drought and that the minhag of Sephardim was not to say a haftorah. Yalkut Yosef Moadim page 545 as well as Yechave Daat 5:40 say that the custom of the sephardim is not to say a haftorah except on tisha b'av where even sephardim have a haftara for shacharit and mincha.
- Yalkut Yosef Moadim page 546
- Mishna Brurah 566:3, Shaare Ephraim 8:107
- Maharik 9:5, Shulchan Aruch O.C. 566:6, Mishna Brurah 566:19, Aruch Hashulchan 566:11, Rivevot Ephraim 3:338:2. Taz 566:7 explains that he can't take the aliya since that kriyat hatorah isn't relevant to him. The Halichot Shlomo Moadim 2:13:footnote 10 says if one ate a small amount of food he may still receive an aliya on a fast day.
- Magen Avraham 566:8 writes that one who is not fasting may receive an aliyah because the torah would have been read even if not for the fast, while the Maamar Mordechai 566:5 disagrees since the content of the Torah reading is for that of a fast day and not for the week's parsha. Mishna Brurah 566:19 says if one was already called up everyone agrees that he may go up. Yalkut Yosef page 549 says that even if you were called up by name, you should explain to them that you are not fasting, and even adds that this applies where you are currently fasting but do not plan on finishing the fast.
- Sh"t Yechave Daat 1:79
- Shulchan Aruch 550:2, Yalkut Yosef Moadim page 530, Aruch Hashulchan 550:2. This is unlike the Ramban in Torat HaAdam (Chavel edition, page 244) who says that all of these fast days last from sunset the night before, and all the activities that are forbidden on tisha b'av are forbidden on these as well. The Shla Taanit 43b says the only reason not everybody accepted this is because it is something that is too hard for all of the congregation to hold, but on a personal level each person should make an effort to refrain from this. Mishna Brurah 550:6 and Kaf Hachayim 550:10 quote this as well but notes that one should continue to wear leather shoes so as not to publicize it too much.
- Piskei Teshuvot 589:1 citing Pri Megadim 612 citing Taz 612:8
- Baer Heitiv 568:22, Kaf Hachayim 549:11, Mishna Brurah 558:50.
- Yalkut Yosef Moadim page 530
- Yechave Daat 3:67. Beer Moshe 8:95 permits leaving a canteen or soda machine open in a camp for those who aren't fasting, and Shevet Hakehati 4:155:1 permits leaving a store open for those not fasting.
- Rav Shlomo Zalman Auerbach quoted in Nishmas Avraham (v. 5, p. 46). Nitei Gavriel (Ben Hametzarim v. 1 p. 54 3:4 fnt. 8) quotes the Debrisiner Rav who permitted it if the person couldn't swallow it without the water, though the Nitai Gavriel disagrees.
- Maharsham (1:123, page 178), Chelkat Yaakov 2:83, Contemporary Halachic Problems (v. 2, p. 26).
- Birkei Yosef 568, Sh”t Yabia Omer Y”D 2:5(6), O”C 4:41 and 10:41, Yalkut Yosef (Kitzur S”A 550:26 and Tefilla 1:89) however, Kaf HaChaim 568:16, Daat Torah (of the Maharsham) 568:1, Sh”t Mishneh Halachot 7:80, Sh”t Shevet Sofer O”C 25, Peninei Halacha (Rabbi Elazar Melamed), Halachos of Brachos (Rabbi Bodner, pg 207, note 39), and Piskei Teshuvot 568:2 rule that one shouldn’t eat it but rather say Baruch Shem. Teshuvot VeHanhagot 1:329 writes that one should taste it, not swallow, and then spit it out. Rav Mordechai Eliyahu quotes the differing opinions and doesn't give a ruling.
- Shulchan Aruch 568:1. Mishna Brurah 568:1 says this also applies if you ate on purpose. Mishna Brurah 568:3 says that you can even say aneinu during the shemoneh esrei during public fast days. Shevet Halevi 5:60 explains that this is only true for someone who began the fast and ate accidentally and not someone who is exempt from fasting. Yabia Omer YD 1:14:8 says you can only recite aneinu if you have eaten less than a kezayit.
- Yalkut Yosef Moadim 535
- Sh”t Yechave Daat 5:39, Sh”t Yabia Omer 1:33. He adds that if it is extremely urgent, one may be lenient on Tisha BeAv after mid-day in private. see Smoking
- S”A 567:1 writes that on any fast day one may taste food up to a Revi'it as long as one spits it all out except for Tisha BeAv and Yom Kippur when it’s forbidden. Rama 567:1 writes that the minhag is not to taste any food on any communal fast. Mishna Brurah 567:6 writes that one may only be lenient in a case where one has to taste food that’s being prepared for a Seudat Mitzvah to see if it’s spiced well. However, Rav Ovadyah in Chazon Ovadyah (Arba Taniyot pg 27) rules like S”A.
- S”A 567:2 quotes a dispute whether one is allowed to taste up to a Revi'it and the Revi'it is a combination of anything one tasted the whole day or that one may taste up to a Revi'it many times if at each time it is less than a Revi'it (according to the explanation of Mishna Brurah 567:7 and 9). Kaf HaChaim 567:12 rules that the halacha follows the second opinion but preferably one should be strict for the first opinion as well. Mishna Brurah 567:8 also implies this.
- Shemirat Shabbat KeHilchata 42:61
- Piskei Teshuvot 550:8 in name of Pri Megadim A”A 551:42 and Kaf HaChaim 550:209
- Rav Chaim Palagi in Ruach Chaim 566:4 is strict. Or Letzion and Piskei Teshuvot 550:8 agree. However, Yalkut Yosef and Tzitz Eliezer 7:49:12 are lenient but still say its preferable not to.
- Mishna Brurah 566:12
- Mishna Brurah 549:1
- The Gemara Brachot 17a records that Rav Sheshet would pray before Hashem that today when there's no Bet Hamikdash He should accept our fasts as though they were korbanot since by fasting a person loses a slight amount of his flesh and blood in order to attain atonement. Gemara Brachot 6b indicates that fasting is certainly a mitvzah, yet giving charity is a crucial element of the fast day.
- Gemara Tanit 11b, Shulchan Aruch 571:2. Mishna Brurah 571:3 clarifies that this applies only to a talmid chacham who is completely involved in learning and it even applies nowadays to such a person. Mishna Brurah 571:4 adds that if a talmid chacham has certain sins for which he needs to fast in order to do teshuva it is permitted to fast.
- Shulchan Aruch 571:2
- Shulchan Aruch 565:6
- Shulchan Aruch 562:5
- Shulchan Aruch 562:6
- Tanit 12a, Shulchan Aruch 562:1
- The Gemara Tanit 11b establishes that a fast of hours counts as a fast in order to recite anenu. However, Rav Chisda explains that it is only a fast of hours if one didn't eat until that day. Therefore, Rashi explains the case of a fast of hours is where one happen to fast until midday and then after he midday he decided to fast the rest of the day. The Rambam (Taniyot 1:13) learns that the gemara is saying that one can have a fast of hours for the end of the day even if ate in the morning. The Rashba (responsa) writes that the Rambam retracted. Shulchan Aruch 562:1 accepts Rashi as the primary opinion. However, the secondary opinion he quotes is the Rosh (Tanit 1:12) who explains that it is always necessary to accept the fast of hours a day in advance for it to count.
- Rav Chisda in Tanit 12a says that it is only a fast if a person completes it upon the night. This is understood by most rishonim (Rashi s.v. ha, Rambam (Taniyot 1:13, Raavad ad loc., Rosh Tanit 1:12) that it doesn't even count as a fast of hours if one eats before the night. However, the Mordechai (Tanit no. 625) and Hagahot Ashri (Tanit 1:12) argues that Rav Chisda only meant that if one accepted to fast for the whole day then it is ineffective if one ate before night, but it is possible to accept just to fast part of the day. The Shulchan Aruch 562:2 quotes this opinion as some say and the Rama 562:2 accepts it so that an individual can recite anenu in shema kolenu but not to change any bracha. Magen Avraham 562:5 writes that minimally the fast has to go from the morning until after Plag Mincha even if one didn't actually daven arvit yet, however, the Eliya Rabba 559:26 and Machasit Hashekel 562:5 hold that it is sufficient if he fasts until mincha gedola. Mishna Brurah 562:10 quotes the Eliya Rabba for someone who is weak.