Sunan Abi Dawud Book 2, Hadith 196
“I used to lead them in prayer with a sheet of cloth on me that was patched and torn. When I prostrated myself, my buttocks were disclosed.
The one of you who knows most of the Qur’an should act as your imam. I knew the Qur’an better than most of them because I had memorized it. They, therefore, put me in front of them, and I would lead them in prayer. I wore a small yellow mantle which, when I prostrated myself, went up on me, and a woman of the clan said: Cover the back side of your leader from us. So they bought an ‘Ammani shirt for me, and I have never been so pleased about anything after embracing Islam as I was about that (shirt). I used to lead them in prayer and I was only seven or eight year old.
Messenger of Allah, who will lead us in prayer? He said: The one of you who knows most of the Qur’an, or memorizes most of the Qur’an, (should act as your imam). There was none in the clan who knew more of the Qur’an than I did. They, therefore, put me in front of them and I was only a boy. And I wore a mantle, Whenever I was present in the gathering of Jarm (name of his clan), I would act as their Imam, and lead them in their funeral prayer until today.
Abu Dawud said: This tradition has been narrated by ‘Amr b. Salamah through a different chain of transmitter. This version has: “When my clan visited the Prophet( may peace be upon him) ....” He did not report it on the authority of his father.