Huyayy ibn Akhtab Convinces Banu Qurayza to Break Their Treaty

During the Battle of the Trench, while Medina was besieged by a massive confederate army of ten thousand fighters, Huyayy ibn Akhtab of the expelled Banu Nadir went to the fortress of Ka'b ibn Asad, chief of Banu Qurayza, to convince him to break the treaty with the Prophet. Ka'b initially refused, praising Muhammad's integrity and fearing the consequences. But Huyayy persisted, swearing an oath that if the Confederates withdrew without victory, he would enter Ka'b's fortress and share their fate. Ka'b eventually agreed and tore up the treaty with the Prophet. When Sa'd ibn Mu'adh, chief of the Aws, was sent to verify the reports, Banu Qurayza confirmed their betrayal with contempt, saying: 'Who is the Messenger of Allah? There is no covenant or agreement between us and Muhammad.' This treachery from the rear while the city was besieged from the front created the most dangerous moment in early Islamic history.