Standing up instead of sitting in a two-rak‘a prayer

Question

If, in the tarawih prayer or any other two-rak‘a prayer, someone stands up instead of sitting (qa‘da), and then he is brought back or returns [to the sitting] himself — if this situation occurs in tarawih or another two-rak‘a prayer, is sajda al-sahw necessary in this case or not? And if it is necessary and was not performed, is the prayer valid or not?

Answer

If in a two-rak‘a prayer, on completing two rak‘as, he did not sit (qa‘da) but stood up out of forgetfulness, and then remembered by himself or remembered through the prompting of one of the muqtadis and sat down, he should perform sajda al-sahw and complete the prayer; otherwise it will be necessary (lazim) to pray this prayer again.

Source: Fatawa Mahmudiyya

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