What does the ma'mum do if he forgets and prostrates while the imam is bowing?
Machine translationRead the Arabic original
Question:
May Allah reward you. The questioner says: A person caught up with the imam at the takbir of ihram, but when the imam bowed in the third rak'ah, that person passed by in forgetfulness and prostrated. What must he do? Knowing that the prayer in question was the obligatory 'Isha' prayer.
Answer:
He is required to go back and bow with the imam, or he owes nothing for that. If he did not bow with the imam and remained prostrating until the imam caught up with him, and he left off the bowing, he must stand up and perform a rak'ah after the imam's taslim. Yes.
May Allah reward you. The questioner says: A person caught up with the imam at the takbir of ihram, but when the imam bowed in the third rak'ah, that person passed by in forgetfulness and prostrated. What must he do? Knowing that the prayer in question was the obligatory 'Isha' prayer.
Answer:
He is required to go back and bow with the imam, or he owes nothing for that. If he did not bow with the imam and remained prostrating until the imam caught up with him, and he left off the bowing, he must stand up and perform a rak'ah after the imam's taslim. Yes.
Source
قناة «العلامة الدكتور صالح الفوزان»، 5692- ماذا يفعل المأموم إذا سها فسجد عند ركوع الإمام؟ - الشيخ صالح الفوزان — youtube.com
The Arabic text is a machine transcription of the audio recording.