|A. Though there are many explanations, Rav Yosef Dov Soloveitchik, zt”l suggested the following in the name of his father Rav Moshe Soloveitchik, zt”l.|
The Talmud Yerushalmi (Pesachim 4:1) writes that the day that a person offers a korban is considered a holiday and one must refrain from doing melacha (certain work-type activities). When a person offers a korban, it is as though he is standing before Hashem and at such a time, it is improper for him to busy himself in trivial matters. The Yerushalmi asks that since the Korban Tamid (daily sacrifice) is brought every day on behalf of all Jews, we should never be allowed to work! The Yerushalmi answers that since this is not possible, each day a delegation (known as anshei ma’amad) was sent to the Beis Hamikdash to watch as the Korban was brought. These representatives stood before Hashem in our place, and only they were forbidden from doing melacha.
When the women refused to contribute to the Golden Calf, yet donated generously to the construction of the Mishkan which was completed on Rosh Chodesh Nissan, they elevated themselves to the status of standing before Hashem. When the korban of Rosh Chodesh was brought, it was as though they were watching, and it was therefore considered their Yom Tov. By refraining every month from doing melacha on Rosh Chodesh, women demonstrate that they are still standing before Hashem. The korban of Rosh Chodesh remains their personal korban, and it is therefore improper for them to perform melacha on Rosh Chodesh.
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