Battle of Banu Qurayzah
In reference to the Banu Quraizah and their treacherous actions during the Battle of Khandaq, Hazrat Mirza Bashir Ahmad Sahib (ra) has written in Sirat Khatamun-Nabiyyin:
“In addition to this, another tactic which Abu Sufyan employed was that he instructed Huyayy bin Akhtab, the Jewish chief of Banu Nazir, to go to the fortresses of Banu Quraizah in the veils of the darkness of night and attempt to bring over the Banu Quraizah with the aid of their chief, Ka‘b bin Asad. Therefore, Huyayy bin Akhtab found an opportunity and arrived at the home of Ka‘b. Initially, Ka‘b refused and said that ‘We have settled a covenant and agreement with Muhammad (sa), and he has always loyally fulfilled his covenants and agreements, therefore, I cannot act treacherously towards him.’
“However, Huyayy painted a picture of lush green gardens to him and gave him such confidence in the imminent destruction of Islam; and presented their own resolve with such force and emphasis that they would not return from Medina until they had obliterated Islam, that ultimately, he agreed. In this manner, the strength of the Banu Quraizah also added to the weight on a scale which was already heavily weighted to one side (i.e., they were already strong materially). When the Holy Prophet (sa) received news of this dangerous treachery of the Banu Quraizah, initially, the Holy Prophet (sa) dispatched Zubair (ra) bin al-Awwam to obtain intelligence in secret two or three times. Then, after this, the Holy Prophet (sa) formally sent Sa‘d (ra) bin Mu‘az and Sa‘d (ra) bin Ubadah, who were chieftains of the Aus and Khazraj tribes along with a few other influential Companions in the form of a delegation towards the Banu Quraizah, and strictly instructed that if there was troubling news, it should not be publicly disclosed when they returned, rather, secrecy should be maintained so that people were not made apprehensive. When these people reached the dwellings of Banu Quraizah and approached Ka‘b bin Asad, this evil man confronted them in a very arrogant manner. When the two Sa‘ds spoke of the treaty, Ka‘b and the people of his tribe turned wicked and said, ‘Be gone! There is no treaty between Muhammad (sa) and us.’ Upon hearing these words, this delegation of Companions set off. Sa‘d (ra) bin Mu‘az and Sa‘d (ra) bin Ubadah then presented themselves before the Holy Prophet (sa) and informed him of the state of affairs in an appropriate manner.”
(Sirat Khatamun-Nabiyyin, Hazrat Mirza Bashir Ahmad (ra), pp. 584-585)
And so, the punishment or the fight against them ensued. During the Battle of Banu Quraizah, Hazrat Sa‘d (ra) bin Ubadah loaded dates upon several camels to send as food for the Holy Prophet (sa) and the Muslims. On that occasion, the Holy Prophet (sa) stated, “What an excellent form of nourishment the date is!”
(Subul al-Hudaa Wa al-Rashaad, Vol. 5, p. 6, Fi Ghazwah Bani Quraizah, Dar-ul-Kutub al-Ilmiyyah, Beirut, 1993)