He had two brothers — al-Rabi and Sallam. Kenana is said to have urged Muhammad to give up the custom during prayer of turning his face toward Mecca in favor of Jerusalem, as had been the custom in Islam at first. After the expulsion of the Banu al-Nadir, of which tribe he was a member, he and his family retired to Khaybar, where they possessed a castle called Qamus. Ibn Ishaq writes about Kenana ibn al-Rabi:
Kenana al-Rabi, who had the custody of the treasure of Banu Nadir, was brought to the apostle who asked him about it. He denied that he knew where it was. A Jew came, to the apostle and said that he had seen Kenana going round a certain ruin every morning early. When the apostle said to Kenana, "Do you know that if we find you have it I shall kill you?" He said "Yes". The apostle gave orders that the ruin was to be excavated and some of the treasure was found. When he asked him about the rest he refused to produce it, so the apostle gave orders to al-Zubayr Al-Awwam, "Torture him until you extract what he has." So he kindled a fire with flint and steel on his chest until he was nearly dead. Then the apostle delivered him to Muhammad b. Maslama and he struck off his head, in revenge for his brother Mahmud
In addition to Ibn Ishaq's narration Al-Tabari writes:
The Prophet gave orders concerning Kenana to Zubayr, saying, ‘Torture him until you root out and extract what he has. So Zubayr kindled a fire on Kenana’s chest, twirling it with his firestick until Kenana was near death. Then the Messenger gave him to Maslamah, who beheaded him. -- Al-Tabari, Vol. 8, p. 122
Al-Mubarakpuri maintains that al-Rabi was bound by agreements between Muhammad and Khaybar to not conceal anything from the Muslims. He was executed, al-Mubarakpuri concludes, for breaching the agreement. Montgomery Watt supports the view that he was executed for concealing the treasure. Shibli Nomani, however, argues that Kenana was put to death because he had killed Mahmud, the brother of Muhammad bin Maslama. Nomani also casts doubt on the accuracy of the story due to its sources. Shortly after the death of Kenana, Muhammad took his widowed wife Safiyya bint Huyayy as his captive, prior to marrying her and granting her emancipation.
Criticism of Ibn Ishaq's Account
In hadith studies, ibn Isḥaq's hadith is generally thought to be "good" and himself having a reputation of being "sincere" or "trustworthy". However, a general analysis of his isnads has given him the negative distinction of being a mudallis, meaning one who did not name his teacher, claiming instead to narrate directly from his teacher's teacher. Concerning his sīra, the most notable and widely discussed criticism was that of his contemporary, Malik ibn Anas, who leveled many accusations against Ibn Ishaq. Malik rejected the stories of Muhammad and the Jews of Medina on ground that they were taken solely based on accounts by sons of Jewish converts. These same stories have also been denounced as "odd tales" later by Ibn Hajar. Malik and others also thought that Ibn Ishaq relied too heavily on the Isra'iliyat.
