Sayyiduna Abu Layla (may Allah be pleased with him) narrates: We were with the Prophet (peace and blessings be upon him) on the day of the Conquest (of Makkah), and he (peace and blessings be upon him) said: "Abu Sufyan is among the arak (toothbrush) trees." So we went in and seized him, and the Muslims began coming up to him, hiding their swords, until they brought him to the Messenger of Allah (peace and blessings be upon him). He (peace and blessings be upon him) said to him: "Woe to you, O Abu Sufyan! I have come to you with (success in) this world and the Hereafter, so accept Islam and you will be safe." Sayyiduna al-Abbas (may Allah be pleased with him) was his friend, so he said: "O Messenger of Allah! Abu Sufyan is a man who loves renown." So the Messenger of Allah (peace and blessings be upon him) sent a herald to announce in Makkah: "Whoever shuts his door is safe, whoever lays down his weapon is safe, and whoever enters the house of Abu Sufyan is safe." Then he (peace and blessings be upon him) sent Sayyiduna al-Abbas (may Allah be pleased with him) with him, until the two of them sat at the bend of the mountain pass. Then Banu Sulaym came forward, and Abu Sufyan asked: "O Abbas! Who are these?" He said: "These are Banu Sulaym." He said: "What have I to do with Sulaym?" Then Sayyiduna Ali bin Abi Talib (may Allah be pleased with him) came forward with the Muhajirun, and Abu Sufyan asked: "O Abbas! Who are these?" He said: "This is Ali bin Abi Talib with the Muhajirun." Then the Messenger of Allah (peace and blessings be upon him) came forward with the Ansar, and Abu Sufyan asked: "O Abbas! Who are these?" He said: "These are the red death; this is the Messenger of Allah (peace and blessings be upon him) with the Ansar." Abu Sufyan said: "You have seen the kingdom of Chosroes and Caesar, but I have never seen a kingdom like the kingdom of your nephew." Al-Abbas (may Allah be pleased with him) said to him: "This is not kingship; rather, it is prophethood."
Hadith Referenceالمعجم الكبير للطبراني / باب السين / 6389