Repeating the prayer when sajda al-sahw was wajib but not performed

Question

(1) The imam in tarawih sat down after completing the first rak‘a; the followers made the imam stand up by prompting him, [and] the imam, having stood, completed the second rak‘a, then gave the salam and finished the prayer without performing sajda al-sahw. In this case is sajda al-sahw wajib or not, and is the prayer valid or not? (2)

Answer

(1) If, as soon as he sat down, they immediately, without delay, prompted him and made him stand up, sajda al-sahw is not wajib; if a delay occurred, sajda al-sahw is wajib. (2) In this case sajda al-sahw was wajib, but now repeating (i‘ada) this prayer is not wajib.

Source: Fatawa Mahmudiyya

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