For the week ending 17 May 2014 / 17 Iyyar 5774

The "Unknown Days" of the Jewish Calendar

by Rabbi Yehuda Spitz
The Color of HeavenArtscroll

This week, an unsuspecting person wishing to catch a minyan, who walks into a random shul in many places around the world, might be in for a surprise. After the Shemoneh Esrei prayer on Monday there was Selichos; on Wednesday there was no Tachanun; and on Sunday again there won’t be Tachanun! Why would this be? No Tachanun generally signifies that it is a festive day[1]; yet, no other observances are readily noticeable. As for the reciting of Selichos on Monday, they are usually reserved for a fast day; yet no one seems to be fasting! What is going on?

The answer is that three separate specific “Unknown Days” happen to fall out on during this apparently chock-full week.


This past Monday was the third and final day of a semi - annual period that many do not even realize exists: a series of “Days of Tefilla” colloquially known as BeHa”B. This acronym stands for Monday (Beis - 2nd day of the week), Thursday (Hei - 5th day of the week), and the following Monday (Beis). These days are observed on the first Monday, Thursday, and Monday following the earliest Rosh Chodesh after Pesach (Rosh Chodesh Iyar), and likewise after Sukkos (Rosh Chodesh Cheshvan).

The custom of utilizing these specific days for Prayer and supplication is already mentioned almost 900 years ago by the Baalei Tosafos, its importance reiterated by the Tur (who refers to BeHa”B as a French-German custom) and unbeknownst to many, actually codified in Halacha by the Shulchan Aruch as a proper minhag[2]!

Whose Minhag Is It, Anyway?

Although both the Tur and Rema call BeHa”B a German-French custom, and the Shulchan Gavoah (cited l’maaseh by the Kaf Hachaim) writes that this was not the minhag in Spain, implying that Sefardim are not beholden to keep BeHa”B[3], nevertheless, it must be noted that the Shulchan Aruch himself must have felt strongly about this minhag of BeHa”B, as aside for spending a whole siman on it – Orach Chaim 492, he also refers to it and its importance in at least two other locations – Orach Chaim 429, 2 and 566, 2 - 4.

Later Sefardic authorities as well, including the Knesses HaGedolah, Pri Chadash and Chida (ad loc.) also discuss its importance. Therefore, this author finds it interesting that the general Sefardic minhag is not say BeHa”B. In fact, the Siman referring to BeHa”B - O.C. 492, is noticeably absent from the Yalkut Yosef’s Kitzur Shulchan Aruch, implying that it is not relevant to the average Sefardi.

And it is not just the general Sefardi populace who do not say BeHa”B. Already in his time, the Taz noted that even among Ashkenazic communities BeHa”B observance was not widespread. More recently, Rav Menashe Klein, in a side point to the issue being addressed in a teshuva, maintains that one who does not observe BeHa”B is not considered “Poresh Min HaTzibbur”, as even nowadays its observance is not prevalent[4]. But, among many Yeshiva communities, and especially in Eretz Yisrael, reciting BeHa”B twice a year is de rigueur.

Why Now?

The reason most commonly mentioned by the Poskim[5]why these days of prayer are following the holidays of Pesach and Sukkos, is that over the extended holidays, when there is a mitzvah of feasting and simcha, it is more likely that people may have stumbled in some area due to improper behavior and inadvertent sin, and BeHa”B is meant to help rectify any possible offense. This idea is based on Iyov (Ch. 1, verse 5) who would bring Korbanos after “Y’mei Mishteh”, or “Days of Feasting”. These sins might be due to a variety of probable offenses including: mingling - at a festive meal or even at a Drasha in the Shul (!), Yom Tov and Chol Hamoed related transgressions, Chilul Hashem, or overabundance of merriment and gastronomical pleasures[6].

Other explanations offered to explain why BeHa”B was established include:

  1. To entreat Hashem to strengthen our bodies especially at the time of changing seasons when many are likely to get sick[7].
  2. To beseech Hashem that we should have abundant harvests after Pesach and plentiful rains after Sukkos[8].
  3. To commemorate Queen Esther’s original 3-day fast (which actually was Pesach time, and not Purim time)[9]. This is pushed off until the first opportunity after Chodesh Nissan. [The Ta’anis Esther that we fast before Purim is not really due to Esther’s actual fast as recorded in the Megillah, but rather to commemorate that when the Jews went to war against the anti-Semites of their day, they fasted].

Yet, interestingly, although BeHa”B is traditionally meant to be a fast day, still, very few actually do fast, as in our generations people are considered weaker. This rationale is found in many sefarim, including the Chavos Yair, Aruch Hashulchan, and Mishna Berura.[10]

In addition, since BeHa”B is based on a minhag and not an actual Biblical source, many make do with Selichos instead, with the majority also reciting Avinu Malkeinu. That is why our fellow walking in would not see any other traditional signs of a fast day.

Monday, Thursday, Prayer Days…

Monday and Thursday are considered especially potent days for prayer, as Moshe Rabbeinu climbed Har Sinai to receive the Torah on a Thursday and returned with it on a Monday[11]. A mnemonic to showcase this is the first pasuk read on a public fast day Haftara (Yeshaya Ch. 55, verse 6) “Dirshu Hashem B’H imatzo” - “Seek out Hashem when He is to be found”. The letters Beis and Hei show that an auspicious time when Hashem may be found is on Monday and Thursday[12]; therefore Mondays and Thursdays are preferable for fasting and prayer. For whichever reason BeHa”B was established, we shouldn’t let this golden opportunity for tefillah to pass us by[13]!

Pesach Sheini

Wednesday, the 14th of Iyar, is dubbed ‘Pesach Sheini[14]’, which commemorates the day when those who were unable to bring the annual Korban Pesach (special Pesach sacrifice - Pascal lamb) at its proper time (Erev Pesach), were given a second chance to offer this unique Korban[15]. Although technically not considered a real holiday, and despite the fact that it is (astonishingly![16]) not listed in the traditional Halachic sources as one of the days that Tachanun is not said, nevertheless, the custom for many is not to say Tachanun on Pesach Sheini[17], in order to ‘tap into’ the merit that this particular day had during the times of the Beis HaMikdash.[18] Although the Pri Megadim[19] maintains that Tachanun should be said on Pesach Sheini - as the original day it is commemorating was only meant for individuals in unique circumstances, and its absence of mention in the traditional Halachic sources as one of the days that Tachanun is not said speaks volumes, nevertheless, most Poskim rule that one should not say Tachanun on this day.

There is a common custom associated with Pesach Sheini - eating Matzah[20]; but that is not noticeable in shul! Another interesting fact about Pesach Sheini is that it is the Yahrtzeit of Rabi Meir Ba’al HaNeis[21] and many visit his grave on that day.

Lag B’Omer

The third of these ‘Unknown Days’ with no other obvious observances during davening except the omission of Tachanun on Sunday, is Lag B’Omer [18th of Iyar][22]. There are several reasons offered for why Tachanun is not said on Lag B’Omer, including[23]:

  1. It’s the day when Rabbi Akiva’s 24,000 students stopped dying[24].
  2. It’s the day when the Mann (manna) started to fall, feeding Bnei Yisrael in the Midbar[25].
  3. It is the day when Rabi Shimon bar Yochai and his son, Rabi Elazar came out of the cave they hid in for 13 years[26].
  4. It is Rabi Shimon bar Yochai’s Yahrtzeit[27]; however, it is important to note that this understanding might actually be based on a simple printing mistake, and many authorities including the Chida and Ben Ish Chai, maintain that Lag B’Omer is not truly hisYahrtzeit![28]
  5. It is the day when Rabi Akiva gave Semicha to his remaining five students (including Rabi Shimon bar Yochai) after 24,000 died, allowing the Torah’s mesorah to perpetuate[29].
  6. It is the day when Rabi Shimon bar Yochai’s hidden Torah, the Zohar, became revealed to the world[30]

In Eretz Yisrael, this quasi-holiday is widely celebrated, with over half-a million people converging on the sleepy mountaintop town of Meron to visit, daven, and dance at the grave of Rabi Shimon Bar Yochai[31], as well as tens of thousands visiting the grave of Shimon HaTzaddik in Yerushalayim.

With enormous bonfires (mostly built by neighborhood children!) seemingly on almost every street corner, Lag B’Omer in Eretz Yisrael has unfortunately become a pyromaniac’s delight and the firefighters’ and asthmatics’ nightmare.

Other locales have a different sort of custom, such as the one in Krakow, Polandto visit the illustrious Rema’s grave on Lag B’Omer, as it is his Yahrtzeit as well[32]. Yet, in most of Chu”tz La’aretz, there is no other real commemoration or observances of this special day, unless one counts the “traditional” game of baseball and subsequent barbeque. So, it is quite possible that our clueless colleague might just wonder about the omission of Tachanun on Lag B’Omer.

Hopefully, by showcasing these relatively “Unknown Days”, this article should help raise awareness and appreciation of them and their customs. Incredibly, as we are climbing upwards in this unique time period of Sefiras HaOmer, in anticipation of Kabbalas HaTorah, Hashem has given us an opportunity to observe a few special yemei tefilla. May we be zocheh to utilize them to their utmost!

[1]For an explanation of the importance of Tachanun, see recent article titled “Tachanun in Yerushalayim”.

[2]Tosafos (Kedushin 81a s.v. sakva), Tur and Shulchan Aruch (O.C. 492, 1). Actually, a BeHa”b of sorts is mentioned even further back, in Maseches Sofrim (Ch. 21, 1- 3), but that seems to be for one specific reason: to commemorate Mordechai and Esther’s three Day fast. See footnote 9. There is an interesting machlokes Rishonim between the Rosh (Taanis Ch. 1, 20) and Mordechai (Taanis, 629) whether BeHa”b is considered a Taanis Yachid or Taanis Tzibbur.

[3]Shulchan Gavoah (O.C. 492, 1, cited in Kaf Hachaim 492, 8). This is additionally mentioned in the Sefer HaToda’ah (vol. 1, pg 157) and Kitzur Shulchan Aruch of Rav R.B. Toledano (vol. 4, 330).

[4]Taz (O.C. 566, 3), Shu”t Mishna Halachos (vol. 3, 15, s.v. u’lfa”d). See also Shu”t Igros Moshe (O.C. vol. 1, 106) for an interesting discussion why the TefillaMevorchin BeHa”B” is still recited the Shabbos prior to BeHa”B even when a chosson is present.

[5]See Rosh (Taanis Ch. 1, 20), Mordechai (Taanis 629), Tur (O.C. 492), Rema (ad loc), Magen Avraham (ad loc, 1), Shulchan Aruch HaRav (ad loc, 1), Mishna Berura (ad loc, 1) and Shaarei Efraim (Ch. 10, 46).

[6]Mingling at a festive meal or even at a Drasha in the Shul (!) is cited by Rashi & Tosafos (Kiddushin 81a s.v. sakva), Yom Tov and Chol Hamoed related transgressions by Elyah Rabba (O.C. 492, 3, citing the Ma’aglei Tzedek), Chilul Hashem by the Tur (O.C. 429, 2), overabundance of merriment by the Mahari”l (Dinei Hayamim Bein Pesach L’Shavuos) and gastronomical pleasures by the Kol Bo.

[7]See Levush (O.C. 492, 1).

[8]See Ra’avyah (Taanis 863), Mordechai (Taanis, 629), Shach (Y”D 220, 31 s.v. v’nirah li), and Sefer HaToda’ah (vol. 1, pg. 156).

[9]Maseches Sofrim (Ch.21, 1 - 3). See also Sefer Minhagei Yisrael (vol. 1, Ch. 26) who opines that according to this reasoning, the reason for the BeHa”B after Sukkos is not for the same reason as the BeHa”B after Pesach. The Ta’anis Esther that we fast before Purim is not really due to Esther’s actual fast as recorded in the Megillah, but rather to commemorate that when the Jews went to war against the anti-Semites of their day, they fasted (see Mishna Berura 686, 2, quoting the Rambam - Hilchos Taaniyos Ch. 5, 5)].

[10]Shu”t Chavos Yair (126), Aruch Hashulchan (O.C. 492, 2), Mishna Berura (566, 6) Shu”t Mishna Halachos (vol. 9, 174) and Nitei Gavriel (Pesach vol. 3, pg. 242). In a similar vein see also Shu”t Noda B’Yehuda (Kamma O.C. 35, s.v. hinei), Shulchan Aruch HaRav (Iggeres HaTeshuva Ch. 3, based on the Yerushalmi Nedarim Ch. 8, 1), and Orchos Rabbeinu (vol. 2, pg. 160, Hilchos Taanis 2).

[11]See Midrash Tanchuma (Parshas Vayera 16), Tosafos Bava Kamma (82b s.v. kday shelo), and Mishna Berura (134, 6).

[12]Matteh Moshe (748). See also Shulchan Aruch (O.C. 560, 3, based on Tosefta Ta’anis Ch. 2, 5) and Tur, Shulchan Aruch and Rema (O.C. 134, 1) that Mondays and Thursdays are preferable for fasting and prayer.

[13]The Sha’arei Teshuva (492, 1) cites the Ra’avad (Tamim Dayim 177) who maintains that “Yechidim and Anshei Ma’aseh” should keep a BeHa”B after Shavuos as well; yet concludes that the prevailing custom is not to. See also Ra’avyah (Taanis 863), Mordechai (Taanis, 629), Beis Yosef (end O.C. 429), Chok Yaakov (492, 1), Shulchan Aruch HaRav (O.C. 492, 1), Magen Avraham (ad loc, 1), Levush (ad loc, 1), Pri Megadim (E.A. ad loc, 1), Chida (Birkei Yosef ad loc, 1), Kaf Hachaim (ad loc, 1) and Mishna Berura (ad loc, 1), who all rule that there is no BeHa”B after Shavuos. Apparently, Zeman Mattan Torah affords less opportunity for nichshal.

[14]See Sefer HaToda’ah (vol. 2, pg. 253) who explains that it is called this as it is the Pesach that falls out in the second month of the year - Iyar. In the Mishna and Gemara (ex. Rosh Hashana 18a) it is referred to as “Pesach Kattan” or “Pesach Ze’ira” (the Small Pesach).

[15]Bamidbar (Beha’aloscha Ch. 9, verses 1 – 15). See Rashi (ad loc. verse 10) and Sefer HaChinuch (Mitzva 380).

[16]The Aruch Hashulchan (O.C. 131, 12) writes that he is astounded that Pesach Sheini is not listed by any of the traditional Halachic sources - [including the Gemara, Rambam, Tur, Shulchan Aruch, or even the Mishna Berura!] as one of the days that Tachanun is not said. However, see Shu”t Mor V’Ohalos (Mahadura Kama 39, Ohel Brachos V’Hoda’os, pg. 37 s.v. ode) who posits that there was no reason to list Pesach Sheini as a day with no Tachanun recited, as it is mentioned explicitly in the Torah (meaning it is obvious that there is no Tachanun)! On the other hand, see Shu”t M’Mayanei Yeshua (3) who posits (and explains at length) that this machlokes (between the Pri Chadash and Pri Megadim et al.) is based on whether or not a “Chag l’Yechidim” would be enough to exempt the tzibbur from Tachanun. He also discusses the differences between Pesach Sheini and Shavuos in regard to reciting Tachanun the week after. See also the Chida’s Moreh B’Etzba (Ch. 8, 222) who states that on Pesach Sheini one should be “yarbeh simcha ketzas, ki kadosh hayom”.

[17]These Poskim include (O.C. 131, ad loc.) the Knesses HaGedolah (Haghos B.Y. 12, citing ‘Minhag Salonika’; however, see Magen Giborim ad loc. 18 who states that the minhag of Eretz Yisrael, Mitzraim and Salonika is to say Tachanun on Pesach Sheini), Pri Chadash (7), Ya’avetz (in his Siddur Beis Yaakov vol. 2, Shaar HaYesod, Seder Chodesh Iyar pg. 103, 21), Shalmei Tzibur (10), Sha’arei Teshuva (19), Beis David (Shu”t 53; cited by the Shaarei Teshuva ibid. and Kaf Hachaim ad loc. 99, who explains that there is no real machlokes regarding minhag Salonika, Mitzraim and Eretz Yisrael, but rather that all agree that Tachanun is not said on the 14th of Iyar as it is the true Pesach Sheini, and those who said it should be recited were actually referring to the 15th of Iyar), Yosef Daas and Yad Shaul (Y”D 401), Chida (Machazik Bracha (5), Butchatcher Rav (Eshel Avraham s.v. nohagin), Daas Torah (7), Shaarei Ephraim (Ch. 10, 27), Shulchan HaTahor (8), Birchas HaPesach (Ch. 16, 5), Aruch Hashulchan (12), Kaf Hachaim (99), and Sefer Ishei Yisrael (Ch. 43, 11). This is also the “Minhag Yerushalayim” - see the Tukachinsky Luach and Halichos Shlomo (on Tefilla, Ch.11, 9 & Moadim vol. 2, Ch. 11, 20). However, it is known that the Chazon Ish did say Tachanun on Pesach Sheini (sefer Bein Pesach L’Shavuos, in the introduction to the sefer titled ‘Hanhagos HaChazon Ish’ by Rav Chaim Kanievsky; also found at the end of Sefer Imrei Yosher, 25 and cited in Orchos Rabbeinu vol. 1, pg. 68). See also Shu”t Rivevos Efraim (vol. 1, 339 & vol. 258) who explains that Tachanun is recited at the Mincha before Pesach Sheini, even according to the majority opinion that it is not said on Pesach Sheini itself, as opposed to most other ‘Moadim’. [Most poskim agree with this as well - see Luach Eretz Yisroel (Chodesh Iyar), Halichos Shlomo (Moadim vol. 2, Ch. 11, Devar halacha 29), and Ishei Yisroel (Ch. 25, 18).] Although not widely followed, there is also an opinion based on the Zohar (Parshas Baha’alosecha, Rayeh Mehemna pg. 152b) that Tachanun should not be said for a full 7 days starting from Pesach Sheini [cited in the Shu”t Mor V’Ohalos (ibid.) quoting Rav Mordechai m’Chernobyl and in Shu”t Divrei Yatziv (O.C. vol. 1, 75, 4 s.v. u’lezeh) quoting the Divrei Chaim of Sanz. The Pischa Zuta (Birchas HaPesach Ch. 16, footnote 6) cites a different reason as well, quoting the Maharsha”k in his Imrei Shefer on Parshas Beha’alosecha. He adds that the Likutei Mahariach (quoting the sefer HaYashar V’HaTov) was a proponent of this minhag as well].

[18]Eshel Avraham ibid.

[19]Pri Megadim (O.C. 131, M.Z. s.v. mah).

[20]See Birchas HaPesach (Ch. 16, 5 s.v. yesh and footnote 7), Sefer HaToda’ah (vol. 2, pg. 253), Shu”t Rivevos Efraim (vol. 2, 129, 39 & vol. 3, 331), Orchos Rabbeinu (vol. 2, pg. 97, 17), Netei Gavriel (Pesach vol. 3, pg. 330), Shu”t Divrei Shalom (vol. 4, 87) and Shu”t Kinyan Torah B’Halacha (vol. 7, 42, 3).

[21]See Shu”t Yaskil Avdi (vol. 5, 54, 1) citing the Sdei Chemed (vol. 1, Asifas Dinim, Ma’areches Eretz Yisrael pg. 4a) that the Beis Knesses and Beis Midrash built over Rabi Meir Ba’al HaNeis’s kever in Teverya were inaugurated on Pesach Sheini and many were kavua a minhag to celebrate every year on that day at his kever, similar to Rabi Shimon bar Yochai’s kever on Lag B’Omer. The Sdei Chemed cites several parallels including celebrating their hidden Torah being revealed to the world (‘ohr ha’meir l’olam, u’meir eini chachamim b’halacha’). Additionally, like Rav Shimon, Rav Meir was one of the five remaining students of Rabi Akiva who received semicha at that time. It is interesting to note that they do not mention Lag B’Omer being the actual Yahrtzeit of Rabi Shimon bar Yochai (see footnote 28).

[22]See Tur/ Shulchan Aruch and Rema and relevant commentaries to O.C. (131, 6, and 493, 2).

[23]There are many sefarim available who give full treatment to the topic of Lag B’Omer, including Bein Pesach L’Shavuos and Nitei Gavriel. It is also worthwhile to read Rabbi Eliezer Brodt’s excellent articles on topic: and, and featured in Ami Magazine # 22.

[24]See Biur HaGr”a (O.C. 131, 6 s.v. b’Lag), Pri Chadash (O.C. 493), Pri Megadim (O.C. 493, M.Z. 1), Shelah (Pesachim 525), Kitzur Shulchan Aruch (120, 6), and Mishna Berura (493, 8).

[25]See Shu”t Chasam Sofer (Y”D 233, s.v. amnam yada’ati).

[26]See Aruch Hashulchan (O.C. 493, 7).

[27]See Chayei Adam (vol. 2, 131, 11), Birkei Yosef (O.C. 493, 4), Aruch Hashulchan (ibid.) and Kaf Hachaim (ad loc. 27).

[28]See the Chida's Shu”t Ma'aris Ha'ayin (7), the Ben Ish Chai's Shu”t Rav Pe'alim (vol. 1, O.C. beg. 11 s.v. Teshuva), and Rav Yaakov Hillel’s ‘Eid HaGal HaZeh’ at length.

[29]See Yalkut Me’am Loez - Parshas Emor and Sdei Chemed – Ma'areches Eretz Yisrael, 6; the Pri Chadash (ibid.) and Chida (Tuv Ayin 17, 493) write that it is the day when Rabi Akiva started teaching his five new talmidim.

[30]See Zohar (Parshas Ha’azinu). See also Bnei Yisaschar (vol. 1, Ma'amarei Chodesh Iyar, Maamar 3: 2, 3, 6 & 7) who explains that this is the reason why the minhag is to "light neiros u'me'oros' on this holy day". The Bnei Yisaschar elaborates further on this minhag, citing several other reasons. Additionally, he posits that Lag B'Omer is also the Rashb'i's birthday.

[31]As per the custom mentioned by Rav Chaim Vital in Sha’ar HaKavannos (pg. 87a); see Ateres Zkainim (O.C. 493, 1), Aruch Hashulchan (O.C. 493, 7), and Kaf Hachaim (O.C. 493, 26). However, there were several authorities who were skeptical at best about this custom, including the Chasam Sofer (Shu”t Y”D 233, s.v. amnam yada’ati) and the Shoel U’Meishiv (Shu”t vol. 5, 39). [See also Shu”t Shaim Aryeh (14) who attempts to answer their criticism.] See also Rav Ovadia Yosef zt”l’s Shu”t Yechaveh Daas (vol. 5, 35) who writes very strongly against going up to Meron on Lag B'Omer. It is also well known that many Rabbanim, including Rav Yosef Shalom Elyashiv zt”l, when asked whether one should go to Meron on Lag B’Omer, replied “Rabi Shimon is duh”, pointing to a Gemara. In other words, if one wants to celebrate Rabi Shimon bar Yochai’s greatness properly on “his day”, they feel that it is preferable to sit and learn his Torah (i.e. learn Gemara). In fact, the Chida (Moreh B’Etzba Ch. 8, 223) mentions such a minhag as well. For a discussion as to the level of Rabi Shimon bar Yochai’s greatness, see Rabbeinu Chananel’s commentary to Sukkah (45b) and Shu”t Rav Pe’alim (vol. 1, Y”D 58 s.v. v’hu pg. 72a) on why he specifically was the one to be zocheh to reveal the Zohar.

[32]See sefer Bein Pesach L’Shavuos (pg. 302).

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