Mishkat al-Masabih
Abu Huraira reported God’s Messenger as saying, “When you come to the prayer and we are prostrating ourselves you must prostrate yourselves without reckoning it as part of your prayer; and if anyone is present at a rak'a he has been present at the prayer.” Abu Dawud transmitted it.
وَعَنْ أَبِي هُرَيْرَةَ رَضِيَ اللَّهُ عَنْهُ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «إِذَا جِئْتُمْ إِلَى الصَّلَاةِ وَنَحْنُ سُجُودٌ فَاسْجُدُوا وَلَا تَعُدُّوهُ شَيْئًا وَمَنْ أَدْرَكَ رَكْعَةً فقد أدْرك الصَّلَاة» . رَوَاهُ أَبُو دَاوُد
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