Just one Halacha on Sefirat Haomer. It is our custom, that Ladies do NOT count Sefirat Haomer. There’s a great Machloket between the Sephardim and the Ashkenazim if ladies make a Beracha on Mitzvat Ase She Hazeman Gerama. Any Mitzvah that’s bound by time, it’s the Minhag of the Ashkenazim based on the Rabenu Tam to make a Beracha. For example, if a lady wanted to shake the Lulav on Succot, according to the Ashkenazim, she’s allowed to shake the Lulav and the Etrog with the the Beracha, ‘Asher Kedishanu Bemitzvotav Vitzivanu Al Netilat Lulav’. For the matter if she wanted to count Sefirat Haomer, she’s not obligated, but she has the right to make it with the Beracha. However, the Sephardim that follow the opinion of Maran, when it comes to this, our ladies do not make a Beracaha.
That’s why there is another Halacha that says, for example, that if a person wants to eat within a half hour of the Omer, we explained many times its forbidden to sit down and start a meal of more than 2 ounces of bread within a half hour of the Haomer. But the Halacha does say if you have a Shomer, if you have somebody that’s going to remind you to count, that you can start to eat, because you already set the Shomer, you set a safety net in motion in order to remind you so you won’t forget. But the Halacha says that you can’t let a lady be a Shomeret for you, because the lady is not obligated in the Omer, and therefore its not going to be on her mind since its not on the mind for herself. It’s not going to be on her mind to tell others. So a lady would not be a Shomeret. You need somebody that’s obligated in the Sefira as well, to designate him as a Shomer. Obviously, he cannot be eating with you. Because if he is eating with you, then he might forget himself, because he has the same problem, so therefore we’re talking about a Shomer that’s not eating with you, that he will be able to remind you. But, a lady, since she is not obligated, she cannot be a Shomeret.
Compare that to Hilchot Shabbat. In Hilchot Shabbat we have a law that says a person is not allowed to read by the light of a candle. Because he might come to flicker the candle, and that’s Asur on Shabbat. However the Halacha says that if he has somebody 9A Shomer) that’s watching him to remind and prevent him if he is about to make the Isur, then its OK. A lady in that case can be a Shomeret. Since a lady is obligated in the laws of Shabbat just as the man is, so therefore its on her mind also, so then she can be the Shomeret. It is told a story, about Chacham Ezra Atia A"H, when he was young he used to learn on Friday nights by the light of the candle. His mother used to be the Shomeret. His mother used to be up into the wee hours of the morning in order that her son would be able to study the Torah with diligence.
