Abdur Rahman bin Harmuz narrates: Abbas bin Abdullah married his daughter to Abdur Rahman bin Hakam, and Abdur Rahman married his daughter to him, and both of them made the marriage itself the dowry. At that time, Sayyiduna Muawiyah bin Abu Sufyan (may Allah be pleased with him) was the Caliph. He wrote a letter to Marwan (the governor of Madinah) and instructed him to separate the two. In his letter, he wrote that this is shighar, which the Prophet Muhammad (peace be upon him) forbade.