It is narrated from Sayyiduna Ubayy bin Ka'b (may Allah be pleased with him) that he said: On the day of Uhud, sixty-four of the Ansar and six of the Muhajirun were martyred, among whom was Sayyiduna Hamzah (may Allah be pleased with him), and the polytheists mutilated their bodies. At this the Ansar said: "If we ever get such an opportunity against them, we will take revenge on them beyond this." Then, when the day of the Conquest of Makkah came, Allah Almighty revealed this verse: "And if you retaliate, then retaliate with the like of what you were made to suffer; but if you are patient, it is certainly better for those who are patient." [Surah al-Nahl: 126] This hadith is sahih (authentic) in its chain of narration, and the two Shaykhs (Bukhari and Muslim) did not record it.