وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ نَافِعٍ، أَنَّ عَبْدَ اللَّهِ بْنَ عُمَرَ، مَرَّ عَلَى رَجُلٍ وَهُوَ يُصَلِّي فَسَلَّمَ عَلَيْهِ فَرَدَّ الرَّجُلُ كَلاَمًا فَرَجَعَ إِلَيْهِ عَبْدُ اللَّهِ بْنُ عُمَرَ فَقَالَ لَهُ إِذَا سُلِّمَ عَلَى أَحَدِكُمْ وَهُوَ يُصَلِّي فَلاَ يَتَكَلَّمْ وَلْيُشِرْ بِيَدِهِ ‏.‏

Yahya related to me from Malik from Nafi that Abdullah ibn Umarpassed by a man who was praying and said, "Peace be upon you," and theman replied to him. Abdullah ibn Umar returned to him and said, "Whensomeone says, 'Peace be upon you' to you while you are praying do notreply, but give a signal with your hand." Translation Not Available

Book Ref: Muwatta Imam Malik Book 9 Hadith 410
Web Ref:  Muwatta Imam Malik Book 9 Hadith 79

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