Hadith 7209
Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) narrates: Previously, Muslims would not look towards Abu Sufyan, nor would they keep his company. He (Abu Sufyan) submitted: O Messenger of Allah! I request three things from you, that you grant them to me. The Prophet (peace and blessings be upon him) asked: What are they? He submitted: My daughter is among the beautiful and attractive women of the Arabs, Umm Habibah; I wish to marry her to you. The Prophet (peace and blessings be upon him) said: Alright. Abu Sufyan submitted: Appoint Muawiyah as your confidant. The Prophet (peace and blessings be upon him) said: Alright. Abu Sufyan submitted: Command me to fight against the polytheists, just as previously I fought against the Muslims. The Prophet (peace and blessings be upon him) said: Alright.