It is said that Ka'b al-Ahbar, who was a Jew before accepting Islam, secretly inserted Israeli traditions into the Ahadith, and he was a hypocrite (نعوذ باللہ). Apparently, wearing the cloak of Islam, he attributed to the Prophet ﷺ in the name of Ahadith things that were actually from the previous scriptures, i.e., the People of the Book (بنی اسرائیل)! And the evidence given for this is that Hazrat Muawiyah (may Allah be pleased with him) mentioned Ka'b al-Ahbar and said: Sometimes his words were false.
Reference: (Sahih Bukhari:7361)
So, when Israeli traditions mixed into the Sunnah, did the Sunnah remain applicable/trustworthy?!
First Point
First of all, it is important to know who Ka'b al-Ahbar was and what the Isra'iliyyat traditions are. Ka'b al-Ahbar's real name was Ka'b ibn Mati' al-Himyari, and he was called Ahbar because he was a learned Jew. He was from Yemen. He left Judaism and accepted Islam, and during the caliphate of Hazrat Umar, he came to Medina and stayed among the Companions. He used to tell the People of the Book (بنی اسرائیل) about matters from their scriptures, which he had access to due to his previous status as a Jewish scholar. These are called Isra'iliyyat traditions. He heard hadiths from the Companions and narrated hadiths from Hazrat Umar, Suhaib, and Umm al-Mu'minin Aisha, may Allah be pleased with them all. Then he went to the land of Sham, where he passed away in 32 AH during the caliphate of Hazrat Uthman.
Reference: (See Siyar A'lam al-Nubala 4/472, Tahdhib al-Tahdhib: 8/438)
In short, Ka'b al-Ahbar was a Tabi'i, as Ibn Sa'd, may Allah have mercy on him, mentioned him among the Tabi'in living in the land of Sham.
Reference: (See Tabaqat al-Kubra 7/309)
The testimony of some Companions confirms his knowledge:
◄ Hazrat Abu Darda, may Allah be pleased with him, said about him: This man from the Himyar tribe has great knowledge.
◄ Hazrat Muawiyah رضي الله عنه says about you: Ka'b al-Ahbar is among the scholars; he possesses knowledge as vast as the ocean.
Reference: (See: Fath al-Bari 13/335)
◄ Hafiz Zahbi states: (کعب الاحبار عمدہ مسلمان اور ٹھوس ديندار عالم دین تھے).
Reference: (See: Siyar A'lam al-Nubala: 3/490)
◄ Hafiz Ibn Hajar رحمه الله mentioned Ka'b al-Ahbar as trustworthy (بااعتماد).
Reference: (See: Taqreeb al-Tahdheeb: 5648)
In short, the majority of the scholars have authenticated Ka'b al-Ahbar, which is why you will not find mention of him in the books of the weak and abandoned narrators.
Second point
After knowing that Ka'b al-Ahbar was a Tabi'i and lived among the Companions of the Prophet, may Allah be pleased with them all, and the Companions used to listen to him regarding the matters of previous scriptures )جن کا انہیں علم تھا(, and this was only possible when he was trustworthy among the Companions, and later scholars have also declared him trustworthy, then what status remains for this baseless accusation?! Did the Companions, whose training was given by the Messenger of Allah ﷺ, not realize that he was a person of ill intent (نعوذباللہ)? And were the Companions so naive, and did they not know and recognize the teachings of the Prophet ﷺ (سنت/احادیث) that they could not distinguish between the teachings of the Prophet ﷺ and anything introduced into them, or see such a thing happening and remain silent about it!
Third Point
To understand the meaning and implication of Hazrat Muawiyah, may Allah be pleased with him, saying about Ka'b al-Ahbar that "sometimes his words were false," it is first necessary to know the entire narration to understand what is being discussed.
Consider the narration:
(روایت کرتے)
Hazrat Muawiyah (may Allah be pleased with him) mentioned Ka'b al-Ahbar and said: Among all those who narrate hadiths from the People of the Book, Ka'b al-Ahbar was very truthful, and despite that, sometimes what he said turned out to be false.
Reference: (Sahih Bukhari:7361)
So the objection is resolved by itself because he is stating that Ka'b al-Ahbar was very truthful in conveying the words of the People of the Book, yet sometimes what he said turned out to be false. This by no means means that Ka'b al-Ahbar used to lie; rather, he acted with complete honesty according to his own understanding. However, since his knowledge was based on those books which had undergone alterations, some of his information turned out to be incorrect. Therefore, instead of confirming this accusation, this narration actually refutes it, because Hazrat Muawiyah (may Allah be pleased with him) describes him not only as truthful but very truthful!
And even if we assume that this is about their lying, there is nothing in this narration that suggests they used to attribute Israeli narrations to the Messenger of Allah ﷺ. Rather, it is clarified that they used to transmit hadiths from the People of the Book.
Fourth Point
As far as the companions of the Prophet, may Allah be pleased with them all, narrating from Ka'b al-Ahbar about those things which he told from previous scriptures, it was also in the light of the teachings of the Messenger of Allah ﷺ(حدیث) because the Prophet ﷺ had permitted it.
Hazrat Abdullah bin Amr, may Allah be pleased with them both, says that the Noble Prophet ﷺ said: "Convey from me, even if it is one verse. And if you can narrate the events of Bani Israel, there is no harm in that. And whoever deliberately lies upon me, let him prepare his place in Hellfire."
Reference: (Sahih Bukhari:3461)
But it is not that the Companions accepted everything they said; rather, they only accepted what was in accordance with Shariah because this was also the teaching of the Prophet ﷺ, as mentioned in the hadith.
Hazrat Abu Hurairah رضي الله عنه narrated that the People of the Book (یہودی) used to read the Torah in Hebrew themselves but would interpret it in Arabic for the Muslims. Upon this, the Holy Prophet ﷺ said, "Do not confirm nor deny the People of the Book, but say (آمنا بالله وما أنزل إلينا), meaning 'We believe in Allah and in what has been revealed to us.'"
Reference: (Sahih Bukhari:4485)
Therefore, all Isra'iliyat come under a decisive rule: those narrations which Islamic Shariah confirms should be confirmed, and those which Islamic Shariah denies should be denied, and regarding other narrations, confirmation or denial should be withheld.
Final point
If any statement of Ka'b al-Ahbar contradicted the words of Allah's Prophet ﷺ, it is proven that the Companions would refute him, as happened regarding the accepted hour on Friday between Hazrat Abu Hurairah رضي الله عنه and Ka'b al-Ahbar; Hazrat Abu Hurairah رضي الله عنه says that I came to Mount Tur and there I met Ka'b al-Ahbar, so we both stayed together for one day. I would narrate to him the hadiths of the Messenger of Allah ﷺ, and he would tell me the matters of the Torah. I said to him: The Messenger of Allah ﷺ said: "The best day on which the sun has risen is Friday... and on this day there is an hour such that if a believer happens to be in that hour and is praying and asks Allah for something, He will surely grant it." Ka'b said:
This is one day every year. I said: No, rather this hour occurs every Friday. Then Ka'b read the Torah and said: The Messenger of Allah ﷺ has spoken the truth.
Reference: (Sunan an-Nasa'i:1431)
This story clearly testifies that the Companions of the Prophet, may Allah be pleased with them, used to verify whatever they heard from Ka'b al-Ahbar.
