Narrated Abu Sa'id Al-Khudri (may Allah be pleased with him): When Banu Qurayza surrendered and came down from their fortress on the condition of arbitration by Sa'd bin Mu'adh (may Allah be pleased with him), the Messenger of Allah (peace and blessings be upon him) sent for him. He (Sa'd) was staying nearby (because he was wounded). Sa'd (may Allah be pleased with him) came riding on a donkey. When he approached the Prophet (peace and blessings be upon him), the Prophet said: "Stand up for your leader (and help him dismount)." So he dismounted and sat near the Messenger of Allah (peace and blessings be upon him). The Prophet (peace and blessings be upon him) said: "These people (Banu Qurayza) have surrendered on your arbitration, so give your judgment concerning them." He said: "My judgment is that all the men who fought should be killed, and their women and children should be taken as captives." The Prophet (peace and blessings be upon him) said: "You have judged according to Allah's command."

Narrated by Aisha (may Allah be pleased with her): During the Battle of the Trench, Sa’d (may Allah be pleased with him) was wounded. A disbeliever of the Quraysh, named Habban bin ‘Ariqah, shot an arrow at him which struck the vein of his arm. The Prophet (peace and blessings be upon him) had a tent pitched for him in the mosque so that he could visit him closely. Then, when the Prophet (peace and blessings be upon him) returned from the Battle of the Trench and had put down his weapons and taken a bath, Jibreel (peace be upon him) came to him, shaking the dust from his head. He said to the Prophet (peace and blessings be upon him),“You have put down your weapons, but by Allah, I have not yet put down mine. You are to march against them.”The Prophet (peace and blessings be upon him) asked,“Against whom?”He pointed towards Banu Qurayza. The Prophet (peace and blessings be upon him) reached Banu Qurayza (and after a severe siege of fifteen days by the Muslim army, the Jews) surrendered by accepting Sa’d bin Mu’adh (may Allah be pleased with him) as the arbitrator. The Prophet (peace and blessings be upon him) gave Sa’d (may Allah be pleased with him) the authority to decide. Sa’d (may Allah be pleased with him) said,“My decision regarding them is that all those capable of fighting among them should be killed, their women and children should be taken captive, and their wealth should be distributed.”

Hazrat Aisha (may Allah be pleased with her) narrated that Hazrat Sa’d (may Allah be pleased with him) made this supplication:“O Allah! You know well that nothing is dearer to me than that I fight in Your path against the people who denied Your Messenger (peace be upon him) and expelled him from his homeland. Now it seems that You have ended the fighting between us and them, but if there remains any part of our battle with the Quraysh, then keep me alive for it, so that I may fight them in Your path. And if You have indeed ended the fighting, then make my wounds fresh again and let me die from them.”After this supplication, his wound on the chest became fresh again. There was also a tent in the mosque belonging to some companions from the tribe of Banu Ghifar. Blood flowed towards them, so they became anxious and said,“O people of the tent! Why is this blood flowing towards us from your side?”When they looked, they saw that blood was flowing from the wound of Sa’d (may Allah be pleased with him), and he passed away from it.