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1114. After the tashahhud in the last rak‘ah of prayer, it is recommended say the following while sitting with a composed body:
اَلسَّلامُ عَلَيْكَ اَيُّهَا النَبِىُّ وَ رَحْمَةُ اللّهِ وَ بَرَكاتُهُ({^ May peace be upon you O prophet, and the mercy of Allah and His blessings.^})
Assalaamu 'alayka ayyuhan nabiyyu wa rahmatullaahi wa barakaatuh
After it, one must say the following:
اَلسَّلامُ عَلَيْنا وَ عَلى عِبادِ اللّهِ الصالِحِينَ({^ Peace be upon us and upon the good doing servants of Allah.^})
Assalaamu 'alayna wa 'ala 'ibaadillahis saliheen
or:
اَلسَّلامُ عَلَيْكُمْ ({^ peace be upon you all. ^})
Assalaamu 'alaikum

It is recommended to add وَ رَحْمَةُ اللّهِ وَ بَرَكاتُهُ (wa rahmatullaahi wa barakaatuh) ({^ and Allah’s mercy and His blessings^}). after saying: اَلسَّلامُ عَلَيْكُمْ. In the event one first proclaims: اَلسَّلامُ عَلَيْنا وَ عَلى عِبادِ اللّهِ الصالِحِينَ, it is recommended to follow it up with: اَلسَّلامُ عَلَيْكُمْ وَ رَحْمَةُ اللّهِ وَ بَرَكاتُهُ.

1115. If a person forgets to say the salÁm for prayers and recollects before the form of the prayer has broken, and he has not deliberately or forgetfully performed an action that would invalidate his prayer, such as turning his back to the qiblah, he should say it and his prayer shall be deemed valid.

1116. If a person forgets the salÁm for prayers and recollects after deliberately or inadvertently performing an action that would invalidate his prayer, such as turning his back to the qiblah, his prayer is invalid. If he recollects after the form of his prayer has broken, without having deliberately or forgetfully performed an act that would invalidate the prayer, obligatory precaution dictates that his prayer be considered invalid nonetheless.