Q&A from the Bais HaVaad Halacha Hotline

Addenda Impedimenta

March 21, 2024

Q When Purim falls on motza’ei Shabbos as it does this year, is Al Hanisim inserted when reciting Birkas Hamazon for se’udah shlishis after nightfall?

A Generally, the insertions in Birkas Hamazon follow the meal’s start. For example, on Shabbos, Retzei is inserted when bentching after nightfall at se’udah shlishis, because bread was eaten at the beginning of the meal while it was still Shabbos (Shulchan Aruch O.C. 188:10).

The same principle applies when Rosh Chodesh falls on motza’ei Shabbos: Retzei is said and Ya’aleh Veyavo is omitted (Mishnah Brurah ibid. 33), at least if one finished eating bread before nightfall. If he continued eating at night, the matter is subject to a three-way machlokess:

• The Bach applies the principle to this case as well; Retzei is inserted and not Ya’aleh Veyavo.
• The Taz (ibid. 7) says both are inserted, Retzei for the bread eaten by day and Ya’aleh Veyavo for the bread eaten by night.
• The Magein Avraham (ibid. 17) argues that the two insertions contradict one another—as Shabbos and Rosh Chodesh fall on different days—so they cannot both be invoked in the same Birkas Hamazon. But how to choose between them? He rules that the meal’s conclusion takes precedence over its start, so say Ya’aleh Veyavo and not Retzei.

There is no universal minhag about which view to follow.

The Mishnah Brurah explains that the Magein Avraham’s ruling does not apply to your case of Al Hanisim and Retzei, because Al Hanisim is a lesser obligation than Retzei.

Later poskim consider whether the Taz’s idea applies to Al Hanisim and Retzei: The Kitzur Shulchan Aruch (44:17) assumes that the Taz’s logic is applicable to all insertions, so Al Hanisim is said along with Retzei. But the Pri Megadim (M.Z. ibid. 7) avers that the combination of Al Hanisim and Retzei is different, and even the Taz would agree that both cannot be said.

In practice, only Retzei should be inserted, because the majority (Bach, Magein Avraham, and Pri Megadim) say that Retzei overrides Al Hanisim (Kovetz Halachos, Purim 17:3).