A Guide to Sefirat HaOmer

today would have been day so-and-so from the bringing of the Omer.” Others maintain that the mitzvah of Sefirat HaOmer continues to be a Biblical obligation. In this view, when the Torah speaks of counting from the bringing of the Omer, this event is referenced only as a calendar date. When we say, “Today is day so-andso from the bringing of the Omer,” in essence we are saying that today is day so-and-so from the second day of Pesach.

The dispute over whether Sefirat HaOmer today is a Biblical or rabbinic obligation has various ramifications, most notably: What is the halacha if there is a safek (uncertainty) if one counted? If the mitzvah is Biblical, the rule is safek dioraisa lichumra (we are stringent), while if it is rabbinic, safek derabbanan likulah (we are lenient) prevails. Most poskim are of the opinion that after the destruction of the Beit HaMikdash, Sefirat HaOmer is a rabbinic (and not a Biblical) obligation.

For this reason, the Mishna Berura (489:15) writes that many people count sefira during bein hashmashot (twilight, between sunset and nightfall). In halacha, this period is considered a safek yom safek laila (uncertain time, possibly day or possibly night). Nonetheless, sefira is counted by many at this time because they follow the opinion that today Sefirat HaOmer is a rabbinic mitzvah. That said, the Mishna Berura (489:14) writes that in any event, it is best to count after nightfall when we are certain it is night. Furthermore, if one counted during bein hashmashot, the Mishna Berura (489:15) recommends repeating the sefira without a bracha after nightfall.

The Talmud (Yevamos 62b) relates that 24,000 students of Rebbe Akiva died from Passover to Shavuot because they did not treat each other with the proper level of respect. For this reason, a period of mourning is observed during sefira. The Kaf Hachaim (493:5) writes that during this time we should focus on treating others with love, kindness, and respect.

The following are some questions that are commonly asked about Sefirat HaOmer.

If one forgot to count one of the days of sefira, can he/ she continue to count with a bracha?

This issue was debated by poskim hundreds of years ago. Sefer Baal Halachot Gedolot (written in the Geonic period) maintains that if a day was missed, one may not continue reciting sefira with a bracha, while Tosafot disagrees. The standard explanation of this dispute is that the Sefer Baal Halachot Gedolot considers the counting of the 49 days of sefira as one extended mitzvah. If even one day was missed, the mitzvah cannot be fulfilled, and therefore one may not continue counting with a bracha. In contrast, Tosafot considers each day to be a separate and independent mitzvah. The Shulchan Aruch (O.C. 489:8) rules that if a day of sefira was missed, one should continue to count sefira in accordance with the opinion of Tosafot, but a bracha should not be recited in deference to the position of the Baal Halachot Gedolot. Nonetheless, it is recommended that one should hear the blessing from someone else since there is still a mitzvah according to Tosafot.

If one is unsure whether he counted, he should continue to count with a bracha (M.B. 489:38 and Beiur Halacha). This is because there is a double uncertainty (known as a sfek sfaika); perhaps he did not forget, and even if he did, possibly the halacha is like Tosafot.

The proper time to count sefira is at night, which is the beginning of the day halachically. Poskim dispute whether the mitzvah of sefira can be fulfilled during the day that follows the night. If a person forgot to count at night and remembered during the day, sefira should be recited that day without a bracha because of the possibility that the mitzvah cannot be fulfilled in the day. Nonetheless, for the remainder of sefira, one would continue to count at night with a bracha. Rav Moshe Feinstein ztz”l (Igrot Moshe O.C. 499:3) discusses an interesting question related to this topic. If a person forgot to count Thursday night, and remembered to count Friday afternoon before sunset but after accepting Shabbat, is the counting valid to the extent that the following days can be counted with a bracha? One can argue that counting after accepting Shabbat is completely invalid, since it is taking place on Shabbat, which is no longer Friday. Rav Moshe rules that the counting is valid. Although the person has accepted the sanctity of Shabbat, nonetheless the day remains Friday until sunset, and sefira can be recited.

When are the periods of mourning in sefira observed?

There are various customs. The main ones are the following: (a) From the first day of the Omer until the 33rd day of the Omer (Lag BaOmer. (b) From the 30th of Nissan (the first day of Rosh Chodesh Iyar) until the morning of the 3rd of Sivan. (c) From the second day of Iyar until the day before Shavuot. (d) From the first day of the Omer until the morning of the 34th day of the Omer (this is the prevailing Sephardic practice). In all these customs—except (d)—the mourning is not observed on the 33rd of the Omer. (Please consult a calendar for the corresponding secular dates for this year.)

Can one recite the blessing of Shehecheyanu during the mourning period of sefira?

The Mishna Berura (493:2) is of the opinion that one is permitted. However, the Ta’amei Ha’Minhagim (p.251) quotes the Eliyaha Zuta (Siman 493) that one should not recite the blessing and refrain from purchasing new clothes during this time. However, the more prevalent custom is to be lenient.

There are various customs of mourning during sefira. May one who is observing mourning in accordance with one minhag attend a wedding of someone who is not in mourning because he follows a different minhag? Also, can a husband and wife follow two different minhagim for the observance of mourning during sefira?

The Igrot Moshe (O.C.1:159) allows one to attend the wedding, because the mitzvah to bring joy to the chattan and kallah overrides the custom of mourning. Regarding the second question, Rav Moshe Feinstein rules that a wife should follow her husband’s minhagim (Igrot Moshe O.C 1:158).

Is it permissible to cut nails during the sefira period?

The Kaf Hachayim (493:16) permits cutting nails during sefira. Only hair cutting is forbidden. Trimming a mustache that interferes with one’s eating is permitted as well (O.C. 551:13).

If I have not yet counted sefira, and someone asked, “What is today’s sefira?” and I answered correctly, can I still count with a bracha? What if it was the 33rd day, and I said it is Lag BaOmer?

1. The Shulchan Aruch (O.C.489:4) writes that if one is asked “What is the sefira?” and responded with the correct date, he has fulfilled the mitzvah. He can no longer recite a bracha and repeat the counting at this point. Even though the person had no intention to fulfill the mitzvah, there is an opinion quoted in the Talmud that mitzvot einam tzerichot kavanah, which means mitzvot can be fulfilled even though a person had no intent to do so. Though the basic halacha follows the opinion that one must have intent to fulfill a mitzvah, with respect to reciting a bracha which may be livatala (in vain), we are more stringent (M.B:22). Therefore, before counting sefira, if asked what day of sefira is it today, one should respond by saying, “Yesterday was day so-and-so.” This is only a concern if responding after sunset, but before sunset, counting sefira is invalid in any event. There is one more consideration in the above situation. The halacha is that if a person counts sefira without saying “Today is day such-and-such,” it is invalid. As such, if one responded to the question of “What day is today?” by only saying “Twenty-three” or “Lag BaOmer” (or whatever day it is), sefira can still be recited with a bracha.

With respect to Lag BaOmer, there is another issue of uncertainty. Lag BaOmer is an abbreviation and not a real date. Whether or not one fulfills the mitzvah of Sefirat HaOmer by saying, “Today is Lag BaOmer” is disputed by poskim, as noted in the Beiur Halacha and Sha’arei Teshuvah (493:6). If counting sefira with an abbreviation is invalid, the bracha can still be recited. However, because this is an unresolved issue, one should be careful not to say “Today is Lag BaOmer.”

When can I get a haircut on Lag BaOmer – in the evening, or must I wait until the morning?

The Shulchan Aruch (O.C. 493:2) states, “Haircutting may not be taken until Lag BaOmer.” The Machatzit HaShekel and the Gra maintain that haircutting is only permitted in the morning on Lag BaOmer. This is because Rebbe Akiva’s students died for thirty-three days and Lag BaOmer is the last day of mourning. Haircutting is permitted in the morning because of the halachic concept, miktzat hayom kekulo, part of the day is treated as an entire day, and only after the morning begins, the mourning is concluded, because we do not apply miktzat hayom kekulo at night. (For the same reason, shiva of a mourner extends only until the morning of the seventh day.) On the other hand, Eliyahu Rabbah (quoted in M.B:11) is of the opinion that the mourning is suspended on Lag BaOmer because Rebbe Akiva’s students died for only thirty-two days. Accordingly, the mourning period of sefira concludes immediately at nightfall on Lag BaOmer, and haircuts are permitted at that time. It has become customary to adopt the more stringent view. When Lag BaOmer falls on Friday, erev Shabbos, there is room to be lenient if there is a strong need to take a haircut Thursday evening (M.B. ibid). Whether a wedding can be performed on the night of Lag BaOmer is a matter of dispute among the poskim (see Igrot Moshe O.C. 1:159).