The Battle of the Trench (al-Ahzab)

The confederate tribes of Arabs and Jews, ten thousand strong, encircled Madinah. The Muslims dug the trench on Salman al-Farisi's advice and held firm for a month in cold and hunger, until Allah turned back the disbelievers in their rage, having attained no good.

A group of the Jews of Banu al-Nadir incited Quraysh, Ghatafan and their followers against Madinah, some ten thousand strong. Salman al-Farisi advised digging a trench before the city on its exposed side. The Prophet ﷺ worked in it with his own hands and the Companions with him in severe hunger, and he promised them, as they struck the rock, the treasures of Chosroes and Caesar.

The confederates were confounded by the trench, a stratagem the Arabs did not know, and the siege dragged on about a month. The trial grew severe with the treachery of Banu Qurayza from within: "and the hearts reached the throats," yet the believers held firm: "This is what Allah and His Messenger promised us."

Then Allah sent upon them a cold, violent wind and hosts they could not see, and Nuʿaym ibn Masʿud — who had secretly embraced Islam — split the word of the confederates, so they withdrew in failure. The Prophet ﷺ said: "Now we shall raid them and they will not raid us." So the Trench marked the turning point in the struggle with Quraysh.