I remembered during bein hashmashos that I didn’t count the night before. What should I do?
By Rabbi Chaim Hillel Raskin, Rov of Anash in Petach Tikvah.
From The Weekly Farbrengen, a publication by Merkaz Anash.
The proper time to count the omer is at the beginning of the night, right after tzeis hakochavim (nightfall), so the counted days will be complete (temimos). Still, one may count until alos hashachar (dawn) with a bracha.1
Although halachically one may count during bein hashmashos (twilight), our custom is wait until nightfall. If one is in a minyan that davens maariv before sunset, he should discreetly not count with them and wait to count later. The minyan should be reminded to count again after nightfall (without a bracha) or at least see to it that by shacharis the minyan should recite the sefira again without a bracha. If it is after sunset (thus bein hashmashos), he should count with the minyan without a bracha and stipulate that it be valid only if he forgets later; otherwise, he doesn’t want to be yotzei so he could count with a brachalater.2
If one missed one night of counting, some hold that all the days of omerare dependent one another, thus one doesn’t fulfill the mitzva by continuing to count. Others, however, view each night independently and hold that he should continue counting with a bracha.3 In practice, one should continue counting without a bracha in line with the rule safek brachos l’hakel.4
If one missed counting at night but remembered the next day, he should count then without a bracha. Since some hold that the time for counting is only at night, the bracha by day is doubtful and omitted. He may nonetheless continue to count in the evenings with a bracha as now it is twofold doubt (sefek sefeika): firstly if day counting is valid, and even if it isn’t, there are still many opinions that hold each night is independent.5 If one is uncertain whether he counted the night before, he continues to count with a bracha for the same reason (a twofold doubt).6
The time of bein hashmashos is doubtful as to which day it belongs. By rabbinic mitzvos, one may after-the-fact consider it part of the previous day, thus may daven mincha if they didn’t yet do so, and one may place an eruv tavshilin.7
There is dispute whether the mitzva of sefiras haomer in the absence of the omer offering is de’oraisa or d’rabanan and the Alter Rebbe rules that the primary opinion is that it is d’rabanan.8 Therefore, if one remembers during bein hashmashos that he didn’t count, he should immediately count the sefira of the previous day (without a bracha) and he may continue the following nights with a bracha. If one is in doubt whether it was still bein hashmashos, he should consult a rav who is familiar with zmanim.9
If one remembered after saying hamapil, he should still count the omer,for we rely on the view that the bracha is about sleep in general and not on one’s own sleep (see issue 474).10
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