Sunan an-Nasa'i 767
It was narrated that 'Amr bin Salamah said:
"When my people came back from the Prophet (ﷺ)they said that he had said: 'Let the one who recites the Quran most lead you in prayer.' So they called me and taught me how to bow and 
prostrate, and I used to lead them in prayer, wearing a torn cloak, and they used to say to my father: 'Will you not conceal your son's backside from us?"'
أَخْبَرَنَا شُعَيْبُ بْنُ يُوسُفَ، قَالَ حَدَّثَنَا يَزِيدُ بْنُ هَارُونَ، قَالَ أَنْبَأَنَا عَاصِمٌ، عَنْ عَمْرِو بْنِ سَلِمَةَ، قَالَ لَمَّا رَجَعَ قَوْمِي مِنْ عِنْدِ النَّبِيِّ صلى الله عليه وسلم قَالُوا إِنَّهُ قَالَ ‏
"‏ لِيَؤُمَّكُمْ أَكْثَرُكُمْ قِرَاءَةً لِلْقُرْآنِ ‏"‏ ‏.‏ قَالَ فَدَعَوْنِي فَعَلَّمُونِي الرُّكُوعَ وَالسُّجُودَ فَكُنْتُ أُصَلِّي بِهِمْ وَكَانَتْ عَلَىَّ بُرْدَةٌ مَفْتُوقَةٌ فَكَانُوا يَقُولُونَ لأَبِي أَلاَ تُغَطِّي عَنَّا اسْتَ ابْنِكَ ‏.‏