ALI MOSQUE (KHANDAQ)
The post of the duel with 'Amr ibn Wudd.
The Most Famous Duel of Khandaq
During the siege, 'Amr ibn Wudd al-'Amiri, one of the greatest warriors of Arabia, crossed the trench on horseback with a few horsemen and challenged the Muslims to single combat.
No Muslim dared to respond. Three times Ali stood up to accept the challenge, and three times the Prophet ﷺ held him back — fearing the loss of such a precious man.
On the third time, the Prophet ﷺ accepted. He wrapped his turban around Ali's head, gave him his sword, and invoked: "O Allah, help him."
Ali killed 'Amr in a battle whose details have been preserved in the Sîrah. The moral defeat of the coalition began that day. (Ibn Hisham · Sîrah)