Sunan an-Nasa'i, Volume 1, Book 10, Hadith 790 (DarusSalam) ⓘ

'Amr bin Salamah Al-Jarmi said: "Riders used to pass by us and we would leam the Qur'an from them. My father came to the Prophet and he said: 'Let the one of you who knows most Qur'an leads the prayer.' My father came and said that the Messenger of Allah had said: 'Let the one of you who knows most Quran lead you in prayer.' They looked and found that I was the one who knew most Qur'an, so I used to lead them in prayer when I was eight years old.'

أَخْبَرَنَا مُوسَى بْنُ عَبْدِ الرَّحْمَنِ الْمَسْرُوقِيُّ، حَدَّثَنَا حُسَيْنُ بْنُ عَلِيٍّ، عَنْ زَائِدَةَ، عَنْ سُفْيَانَ، عَنْ أَيُّوبَ، قَالَ حَدَّثَنِي عَمْرُو بْنُ سَلِمَةَ الْجَرْمِيُّ، قَالَ كَانَ يَمُرُّ عَلَيْنَا الرُّكْبَانُ فَنَتَعَلَّمُ مِنْهُمُ الْقُرْآنَ فَأَتَى أَبِي النَّبِيَّ صلى الله عليه وسلم فَقَالَ ‏"‏ لِيَؤُمَّكُمْ أَكْثَرُكُمْ قُرْآنًا ‏"‏ ‏.‏ فَجَاءَ أَبِي فَقَالَ إِنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏"‏ لِيَؤُمَّكُمْ أَكْثَرُكُمْ قُرْآنًا ‏"‏ ‏.‏ فَنَظَرُوا فَكُنْتُ أَكْثَرَهُمْ قُرْآنًا فَكُنْتُ أَؤُمُّهُمْ وَأَنَا ابْنُ ثَمَانِ سِنِينَ ‏.‏