Sahih Muslim , Book 31, Hadith 6178 (USC-MSA)

Abu Huraira reported: We were sitting in the company of Allah's Apostle that Sura al-Jumu'a was revealed to him and when he recited (these words):" Others from amongst them who have not yet joined them," a person amongst them (those who were sitting there) said: Allah's Messenger! But Allah's Apostle made no reply, until he questioned him once, twice or thrice. And there was amongst us Salman the Persian. The Apostle of Allah placed his hand on Salman and then said: Even if faith were near the Pleiades, a man from amongst these would surely find it.

حَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، حَدَّثَنَا عَبْدُ الْعَزِيزِ، - يَعْنِي ابْنَ مُحَمَّدٍ - عَنْ ثَوْرٍ، عَنْ أَبِي الْغَيْثِ، عَنْ أَبِي هُرَيْرَةَ، قَالَ كُنَّا جُلُوسًا عِنْدَ النَّبِيِّ صلى الله عليه وسلم إِذْ نَزَلَتْ عَلَيْهِ سُورَةُ الْجُمُعَةِ فَلَمَّا قَرَأَ ‏{‏ وَآخَرِينَ مِنْهُمْ لَمَّا يَلْحَقُوا بِهِمْ‏}‏ قَالَ رَجُلٌ مَنْ هَؤُلاَءِ يَا رَسُولَ اللَّهِ فَلَمْ يُرَاجِعْهُ النَّبِيُّ صلى الله عليه وسلم حَتَّى سَأَلَهُ مَرَّةً أَوْ مَرَّتَيْنِ أَوْ ثَلاَثًا - قَالَ - وَفِينَا سَلْمَانُ الْفَارِسِيُّ - قَالَ - فَوَضَعَ النَّبِيُّ صلى الله عليه وسلم يَدَهُ عَلَى سَلْمَانَ ثُمَّ قَالَ ‏"‏ لَوْ كَانَ الإِيمَانُ عِنْدَ الثُّرَيَّا لَنَالَهُ رِجَالٌ مِنْ هَؤُلاَءِ ‏"‏ ‏.‏

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