Sayyiduna Ali bin Abi Talib (may Allah be pleased with him) narrates: A Coptic man used to come and go frequently to Umm Ibrahim, Sayyidah Mariyah; he was her cousin, and he used to come to visit her. The Prophet (peace and blessings be upon him) said to Sayyiduna Ali (may Allah be pleased with him): "Take this sword and go, and if you find that man with that woman, kill him." Sayyiduna Ali (may Allah be pleased with him) says: I said: "O Messenger of Allah! Regarding this command of yours, I have become like a heated iron; nothing will turn me back until I carry out the command you have given me. Or is it that the one present sees what the absent one does not see (that is, may I also decide at my own discretion)?" The Prophet (peace and blessings be upon him) said: "Rather, the one present sees what the absent one does not see (that is, you may also decide at your own discretion)." Sayyiduna Ali (may Allah be pleased with him) says: I set out carrying the sword. I found that man with that woman, and I drew the sword. When he saw me coming towards him, he realised what I intended. He went to a tree and climbed it, then he jumped from it and fell on the back of his neck; his legs spread apart, and he turned out to be a man who had no private parts, neither little nor much. I put the sword back in its sheath, then I came to the Prophet (peace and blessings be upon him) and told him about it. The Prophet (peace and blessings be upon him) said: "All praise belongs to Allah Almighty alone, who has turned this away from us, the People of the House (Ahl al-Bayt)."
Bazzar recorded it; its chain contains a narrator, Ibn Ishaq, who is a mudallis (one who conceals defects in the chain) but he is thiqah (trustworthy). The remaining narrators of this report are thiqat (trustworthy). Diya' al-Maqdisi recorded it in al-Ahadith al-Mukhtarah.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب النكاح / 7732