Mishkat al-Masabih
He reported God's Messenger as saying, “When you tell your companion on Friday to be silent while the imam is preaching, you are guilty of idle talk." (Bukhari and Muslim.)
وَعَنْ أَبِي هُرَيْرَةَ رَضِيَ اللَّهُ عَنْهُ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: " إِذَا قُلْتَ لِصَاحِبِكَ يَوْمَ الْجُمُعَةِ أنصت وَالْإِمَام يخْطب فقد لغوت)
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