Ali bin Husayn (may Allah have mercy on him) says: I came to Marwan bin al-Hakam (may Allah have mercy on him), and he said: I have not seen anyone more noble in victory than your father (may Allah be pleased with him), (as shown by) what he did on the day of the Camel: he had it announced that no one fleeing was to be pursued and no wounded man was to be killed.
Imam al-Shafi'i (may Allah have mercy on him) said: I mentioned this hadith to al-Darawardi, and he said: How well he has preserved it! — marvelling at his memory. This is how Ja'far narrated it with this chain. Al-Darawardi said: Ja'far informed us from his father that Sayyiduna Ali (may Allah be pleased with him) used not to take the spoils (salab) of the slain, that he took part in the fighting himself, and that he would not finish off a wounded man nor kill one who fled.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قتال أهل البغي / 16746