Musnad Ahmad 1498

It was narrated that Isma"eel said: l heard Qais bin Abi Hazim say: Sa"d said: I was one of the first seven to embrace Islam with the Messenger of Allah (ﷺ), and we had no food except the leaves of al-hublah (a desert tree), and one of us would produce stools like a sheep, so dry that nothing stuck to it. And now Banu Asad are teaching me about my religion, in which case I must have been doomed and my efforts wasted.