Sayyiduna Abu Juhayfah (may Allah be pleased with him) said: I asked Sayyiduna Ali (may Allah be pleased with him), and in the narration of Ibn Shayban: I said to Ali (may Allah be pleased with him): Do you have anything from the Prophet of Allah (peace and blessings be upon him) other than the Qur'an? He said: No, by the One who splits the seed and creates living beings, except the understanding of the Book of Allah that Allah gives to His servant, and what is in the scroll. I asked: What is written in the scroll? He said: "Blood money, freeing captives, and that a Muslim is not to be killed in return for a disbeliever."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجنايات / 15907