The mitzvah of Sefirat Ha'Omer demands a nightly count of the days between Pesach and Shavuot. As such, the counting must ostensibly be performed at a time that is halachically considered night. This article will discuss the various opinions regarding the earliest time to perform Sefirat Ha'Omer. This question is not only relevant to those congregations who recite the Ma'ariv prayer immediately after Mincha, it is also relevant to those who accept Shabbat early in the summer months and conclude Ma'ariv prior to sundown.

Sefirat Ha'Omer Prior to Sundown
The time period between sundown (shekiat hachama) and nightfall (tzeit hakochavim) is known as bein hashmashot. This time period is considered safek yom v'safek laila (it is halachically doubtful as to whether it is considered day or night). Ostensibly, if one wants to fulfill the mitzvah of Sefirat Ha'Omer with certainty, one must wait until tzeit hakochavim. In fact, Rashba, Teshuvot HaRashba 1:154, rules that if one performs Sefirat Ha'Omer prior to the proper time, there is no fulfillment of the mitzvah. He states that therefore, those who are meticulous wait until tzeit hakochavim to perform the mitzvah of Sefirat Ha'Omer. Rashba's ruling is codified by Shulchan Aruch, Orach Chaim 489:2.

R. Shimshon Ben Tzadok, Tashbetz Katan no. 394, suggests that there is no need to wait until nightfall to perform Sefirat Ha'Omer. According to many Rishonim, the mitzvah of Sefirat Ha'Omer in the absence of the Korban Ha'Omer is only rabbinic in nature (see last year's issue "The Mitzvah of Sefirat Ha'Omer"). Therefore, Tashbetz Katan suggests that since bein hashmashot is considered safek yom v'safek laila, one may be lenient and perform the mitzvah during this time based on the principle of safek d'rabanan l'kula (on matters of rabbinic law, one may be lenient in cases of doubt).

R. David Avudraham, Tefillot HaPesach, cites Tashbetz Katan's suggestion as normative. He then writes that if one finds himself praying with a congregation who performs Sefirat Ha'Omer "before the end of the day" (mibe'od yom), he should perform the Sefirah with the congregation without a beracha on condition that if he remembers to perform Sefirat Ha'Omer after nightfall, he will perform the mitzvah again while reciting a beracha. If in fact he neglects to perform the mitzvah after nightfall, he is considered to have counted with the Sefirat Ha'Omer that he performed with the congregation. R. Avudraham's ruling is codified by Shulchan Aruch, Orach Chaim 489:3.

One can question Shulchan Aruch's codification of both Rashba's opinion and R. Avudraham's opinion. Rashba is clearly of the opinion that one cannot fulfill the mitzvah of Sefirat Ha'Omer until tzeit hakochavim. Accordingly, there is no justification for a congregation to perform Sefirat Ha'Omer before nightfall. In fact, Rashba, in a different responsum (1:235) questions the practice recommended by R. Avudraham. R. Avudraham's suggestion is clearly based on the opinion of Tashbetz Katan that one can fulfill the mitzvah of Sefirat Ha'Omer prior to tzeit hakochavim during the bein hashmashot period. How then can Shulchan Aruch codify both the opinion of Rashba and R. Avudraham?

Mishna Berurah (489:16 and Biur Halacha 489:3 s.v. mibe'od yom) presents two resolutions to this problem. First, Shulchan Aruch is of the opinion that in principle, Tashbetz Katan is correct and one can fulfill the mitzvah of Sefirat Ha'Omer during the bein hashmashot period. Nevertheless, those who are meticulous should wait until tzeit hakochavim to fulfill the mitzvah. For this reason it is justifiable for the congregation to perform Sefirat Ha'Omer during the bein hashmashot period because if Sefirat Ha'Omer is omitted from the Ma'ariv service, people will inevitably forget to perform the mitzvah after tzeit hakochavim. At the same time, those who are meticulous and want to fulfill the mitzvah after tzeit hakochavim should count without reciting a beracha lest they forget to perform the mitzvah after tzeit hakochavim.

Second, R. Avudraham's suggestion is not regarding the bein hashmashot period but rather the period prior to sundown. Although everyone agrees that one cannot fulfill the mitzvah prior to sundown, a minhag developed that Sefirah is recited in the congregation. The minhag developed based on the concern that those who attend Ma'ariv services prior to sundown may not perform Sefirah after nightfall and the mitzvah will be forgotten entirely. Those who are in attendance should count without reciting a beracha since there is no fulfillment of the mitzvah. When nightfall arrives, they should perform the mitzvah and recite a beracha. According to this explanation, those who only count with the congregation don't really fulfill the mitzvah.

Mishna Berurah seems to side with the first explanation. Accordingly, a meticulous individual who finds himself in a congregation that performs Sefirat Ha'Omer before tzeit hakochavim should count without reciting a beracha on condition that the counting should only be effective if he neglects to count after tzeit hakochavim. After tzeit hakochavim he may perform the mitzvah and recite a beracha. The shaliach tzibbur will perform Sefirat Ha'Omer and recite a beracha. When tzeit hakochavim arrives, he is not obligated to perform Sefirat Ha'Omer again. [Mishna Berurah 489:15, notes that Eliah Rabbah 489:10, is of the opinion that after tzeit hakochavim he should count again without reciting a beracha, but he implies that most Acharonim don't require repetition of Sefirah after tzeit hakochavim]

If a congregation accepts Shabbat early and finishes Ma'ariv before sundown, according to the conclusion of Mishna Berurah, there is ostensibly no legitimate justification to perform Sefirat Ha'Omer and recite a beracha. However, Hagahot L'Sefer HaMinhagim (Tirnau) note 21, cites the practice of Ra'avan who performed Sefirah before sundown after accepting Shabbat even though he did not perform Sefirah before sundown the rest of the week. The author of the Hagahot suggests that the reason to distinguish between Shabbat and the rest of the week is because acceptance of Shabbat has the ability to transform the day into night according to some Rishonim (see "Tosefet Shabbat" Part I). The opinion of Ra'avan notwithstanding, Mishna Berurah 489:18, rules that there are no special leniencies when one accepts Shabbat early.

The Actual Time of Tzeit HaKochavim
There is a well known dispute between Rabbeinu Tam (cited in Tosafot, Pesachim 94a s.v. R. Yehuda) and the Vilna Gaon, Biur HaGra, Orach Chaim 261:2, regarding the actual time of tzeit hakochavim. According to the Vilna Gaon, tzeit hakochavim occurs shortly after sundown, whereas according to Rabbeinu Tam, tzeit hakochavim does not occur until much later.

Birkei Yosef, Orach Chaim 489:12, cites Acharonim who are of the opinion that even those who normally follow the stringencies of Rabbeinu Tam's opinion do not necessarily wait to perform Sefirat Ha'Omer according to Rabbeinu Tam's tzeit hakochavim. This leniency is based on the original leniency of Tashbetz Katan to perform Sefirat Ha'Omer during bein hashmashot. This leniency goes one step further by allowing even the meticulous individual to perform Sefirat Ha'Omer at the tzeit hakochavim of the Vilna Gaon.

Some communities follow this practice and will time the completion of Ma'ariv with the tzeit hakochavim of the Vilna Gaon. There are various opinions regarding the actual time of tzeit hakochavim of the Vilna Gaon. They range from nine minutes after sundown (in New York- see Igrot Moshe, Orach Chaim 4:62) to thirty-five minutes after sundown (see R. Yechiel M. Tucatzinski, Bein Hashmashot ch. 8). Based on the aforementioned leniency, even if one follows a later version of the Vilna Gaon's tzeit hakochavim for certain areas of Halacha, there are grounds to accept an earlier time for the Vilna Gaon's tzeit hakochavim for the purpose of Sefirat Ha'Omer (see R. Tucatzinski, ibid).