Sefirat HaOmer Guide: Key Laws for Counting Correctly Every Night

Question: Should one count the Omer at the beginning of the night?

Answer: Ideally, one should count the Omer as early as possible at the beginning of the night, in order to fulfill the verse “temimot tihyenah” (“they shall be complete”). However, Maariv is prayed first, since it is the more frequent mitzvah.

Sources: Mishnah Berurah 489:2; Biur Halacha 489:1; Kaf HaChaim 489:12.

Notes: Ideally one should pray Maariv at the beginning of the night. Even if Maariv is prayed later, one should still count the Omer after Maariv.

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Question: If someone recites the blessing on counting the Omer but does not know which day it is, and only after the blessing hears the correct day from someone else and then counts properly — does it count?

Answer: Ideally, one should not recite the blessing unless they know which day it is. However, after the fact, the obligation is fulfilled.

Sources: Mishnah Berurah 489:29; Sha’ar HaTzion 489:37.

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Question: Is it permitted to pause between the blessing and the counting?

Answer: One may not delay between the blessing and the counting longer than the time it takes to say a short phrase, even in silence.

Sources: Mishnah Berurah 489:29.

Notes: This rule applies to all mitzvah blessings — there should be no significant interruption between the blessing and performing the mitzvah.

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Question: If someone mistakenly says on the fifth day, “Today is four days of the Omer,” what should they do?

Answer: If they realize the mistake immediately, they should correct it without a new blessing. If they realize only afterward, they must count again with a blessing.

Sources: Mishnah Berurah 489:32.

Notes: If corrected immediately, it is sufficient to say “five days” without repeating the word “today.”

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Question: If someone says the correct number of days but the wrong number of weeks — or vice versa, have they fulfilled the mitzvah?

Answer:

• In the middle of the week, they have fulfilled the obligation after the fact.

• At the end of the week:

• If they erred in the number of weeks — there is a dispute whether they fulfilled the obligation.

• If they erred in the number of days — they have not fulfilled the obligation.

Sources: Mishnah Berurah 489:7, 9, 38; Sha’ar HaTzion 489:11, 28; Biur Halacha 489:8.

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Question: For someone who observes mourning customs during the Omer until Lag BaOmer, is it permitted to listen to music afterward?

Answer: Although haircuts are permitted after Lag BaOmer, there is uncertainty whether dancing and optional celebrations should be permitted until Shavuot.

Sources: Sha’ar HaTzion 493:4; Shulchan Aruch O.C. 560:3; Kaf HaChaim 493:9–13.

Notes: Generally, music should not be listened to throughout the Omer period — even on days when haircuts are permitted. However, on Lag BaOmer itself, it is permitted.

The laws of Sefirat HaOmer emphasize precision, awareness, and continuity. From the correct timing to avoiding interruptions and handling mistakes, each detail ensures that the counting remains meaningful and complete — reflecting both discipline and spiritual preparation for Shavuot.