Daily Halacha - Laws of Rosh Hashanah, 23 Elul 5777

When Rosh Hashanah falls on Thursday and Friday and one has prepared an Eruv Tavshilin, is it permissible to prepare one's needs for Shabbat on Thursday?

It is obligatory for every Jew to properly prepare an Eruv Tavshilin before the holiday begins. If Rosh Hashanah falls on Thursday and Friday, it is forbidden to slaughter, bake, or cook on Thursday (the first day of the holiday) for the needs of Shabbat, even if one has prepared an Eruv Tavshilin. Rather, one should cook for Shabbat on the second day of the holiday, which is Friday. Even in cases where there is some constraint that would prevent one from preparing for Shabbat on Friday, for whatever reason, it remains forbidden to do so on Thursday. [Yechaveh Da'at, Volume 6, Section 32].

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