Sayyiduna Ali (may Allah be pleased with him) said that I used to have a lot of madhi (pre-seminal fluid). Since the daughter of the Prophet (peace and blessings be upon him) was married to me, I felt shy to ask the Prophet (peace and blessings be upon him) about this issue myself. So I asked Sayyiduna Miqdad (may Allah be pleased with him) to ask the Prophet (peace and blessings be upon him) about this issue. Accordingly, he asked about this issue, and the Prophet (peace and blessings be upon him) said: "Such a person should perform wudu (ablution)."