297. Forgetting R’tzei and Yaaleh v’Yavo

44:12 If one neglected to say R’tzei on Shabbos or Yaaleh v’Yavo on yom tov, if he realized his mistake before saying God’s Name in the conclusion of the bracha Boneh Yerushalayim, he should go back and say R’tzei and/or Yaaleh v’Yavo as appropriate and continue, repeating the blessing of Boneh Yerushalayim that he had already partially recited. If, however, he already said God’s Name in the conclusion of Boneh Yerushalayim, he should finish that bracha and proceed as follows. On Shabbos, he should recite “Blessed are You, Hashem our G-d, King of the Universe, Who gave Shabbos to His nation Israel for rest, in love, as a sign and a covenant. Blessed are You, Hashem, Who sanctifies Shabbos.” On yom tov, one would say, “Blessed are You, Hashem our G-d, King of the Universe, Who gave the Festivals to His nation Israel, for happiness and rejoicing, this day of (name of Festival). Blessed are You, Hashem, Who sanctifies Israel and the seasons.” If it’s both yom tov and Shabbos and one forgot to say both R’tzei and Yaaleh v’Yavo, he should recite “Blessed are You, Hashem our G-d, King of the Universe, Who gave Shabbos to His nation Israel for rest, in love, as a sign and a covenant, and Festivals for happiness and rejoicing, this day of (name of Festival). Blessed are You, Hashem, Who sanctifies Shabbos, Israel, and the seasons." If, on a day that is both Shabbos and yom tov, one only forgot to say R’tzei or Yaaleh v’Yavo, he would only say the make-up prayer for the one he missed. (See the Kitzur Shulchan Aruch for the text of these prayers in Hebrew.)

44:13 If one forgot to say R’tzei and/or Yaaleh v’Yavo, and did not realize it until after beginning the fourth bracha of bentching, even if all he has said so far is the word “Baruch” of that blessing, he can no longer recite the make-up prayers described above. (There is some discussion of this matter – see Bi’ur Halacha 188:6 s.v. ad she’hischil, and Mishnah Brurah 188:23.) Instead, if one is bentching after one of the first two meals, he must return to the beginning and start over. If he only said the words “Baruch Atah Hashem” of the fourth bracha, he should complete it by saying “lamdeini chukecha,” which is a Biblical verse (Psalms 119:12) and prevents him from having said God’s Name in vain. If he forgot during the third meal, he need not go back. This is because on Shabbos one need not necessarily eat bread at shalosh seudos, and on yom tov one need not eat shalosh seudos at all. (That one need not eat bread at shalosh seudos on Shabbos is not a universal position but we rely on that opinion in this circumstance so as not to be left with an unresolved problem – Mishnah Brurah 188:31.) Nevertheless, if one realized his error while he can still recite the make-up prayer, he must do so regardless of how many meals he has eaten.