Sha’hi reported on the authority of Abu Juhayfh that he asked Sayyidina Ali “0 commander of the Faithful! Do you have anything written down that is not in the Quran?” He said, By Him Who split the seed and created the soul, I am not aware of anything that is not in the Quran. However, we are given the understanding of the Qur’an that Allah grants to any human being. Some things are written down with us.” He asked what they were and he said, ‘Diyat, release of captives and that a Muslim must not be killed for a disbeliever.”
[Nisai 4758, Ibn e Majah 2658]
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