Musannaf Ibn Abi Shaybah 39593 — The Battle of the Trench

It is narrated from Ikrimah that on the day of al-Khandaq, a man from the polytheists stood up and asked: "Who will come out to duel?" He (peace and blessings be upon him) said: "O Zubayr, stand up." Sayyidah Safiyyah (may Allah be pleased with her) said: "O Messenger of Allah (peace and blessings be upon him), I have only one son." He (peace and blessings be upon him) said: "O Zubayr, stand up." So Sayyiduna al-Zubayr (may Allah be pleased with him) stood up, and the Prophet (peace and blessings be upon him) said: "Whichever of the two gets above his opponent will kill him." Sayyiduna al-Zubayr (may Allah be pleased with him) got above him and killed him. Then Sayyiduna al-Zubayr (may Allah be pleased with him) brought the slain man's belongings, and he (peace and blessings be upon him) awarded those belongings to him.