جامع الترمذي

Abu Juhaifah said: "I said to 'Ali: O Commander of the Believers! Do you have anything written that is not in Allah's Book?' He said: 'By the One Who splits the seed and creates the soul, I have not learned from it except what understanding of the Qur'an Allah gives to a man, and what is in this sheet of paper.' I said: 'What is in the paper?' He said: 'It is the 'Aql, the (ransom for) release of captives, and the judgement that no believer is killed for a disbeliever.'"