Musnad Ahmad 930:10

Abdullah narrated to us, Abu Salih Hadiya ibn Abd al-Wahhab al-Marwazi narrated to us, al-Fadl ibn Musa narrated to us, Isa ibn Ubayd narrated to us, from al-Rabi ibn Anas, from Abu al-Aliyah, from Ubayy ibn Ka’b, who said: When the day of Uhud occurred, sixty-four men from the Ansar were killed, and six from the Muhajirun. The companions of the Messenger of Allah (peace and blessings of Allah be upon him) said: "If we have a day like this against the polytheists, we will surely increase upon them [in retaliation]." When the day of the Conquest [of Mecca] arrived, a man who was not known said: "There is no Quraysh after today." Then the announcer of the Messenger of Allah (peace and blessings of Allah be upon him) called out: "Security for the black and the white, except for so-and-so and so-and-so," naming some people. Then Allah, Blessed and Exalted is He, revealed: "And if you punish, then punish with an equivalent of that with which you were harmed. But if you are patient, it is better for those who are patient" [An-Nahl: 126]. The Messenger of Allah (peace and blessings of Allah be upon him) then said: "We shall be patient and we shall not punish."