The follower’s sajda al-sahw before the imam

Question

A man prays together with the imam. No sajda al-sahw arose for the imam, but the follower made a mistake that made sajda al-sahw necessary (lazim), and the follower, out of ignorance, performed sajda al-sahw behind the imam. Was his prayer valid or not?

Answer

Sajda al-sahw was not necessary (lazim) for him. If he performed sajda al-sahw independently before the imam’s salam, his prayer has become invalid (fasid).

Source: Fatawa Mahmudiyya

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