Completing the prayer after a forgetful salam

Question

If in a four-rak‘a prayer one forgetfully gives the salam after two [rak‘as], turns one’s face away from the qibla and walks off, and then remembers — may one build (bina’) upon it or not? In Tahtawi it is written that as long as he has not left the mosque, it is permissible.

Answer

The same is written in other books as well: see al-Bahr, al-Tahtawi ‘ala al-Durr al-Mukhtar, al-Munya, al-Ghunya and others.

Source: Fatawa Mahmudiyya

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