Some of the Mujasima have latched onto the opinion of Ibn Al-Salah, who believed that reports found in Sahih Bukhari and Sahih Muslim are all decisively reliable (Qat’iat Al-Thubut). Ibn Al-Salah‘s reasoning: there is consensus (Ijma’) on the reliability of the two books, so all of the singular reports contained within are decisively reliable by virtue of this consensus.
Know that the above is a weak opinion, which most scholars disagree with. Imam Al-Nawawi’s response to Ibn Al-Salah’s position is recorded in Al-Suyuti’s Tadrib Al-Rawi (Vol. 1, pg. 142):
|Al-Nawawi said: And most scholars disagreed with Ibn Al-Salah, saying: “a report is indecisive as long as it is not mass transmitted”.
And he [Al-Nawawi] said in his commentary of Sahih Muslim: Such is the state of the singular narration. And it makes no difference whether it is reported by the two sheikhs [Bukhari and Muslim] or anyone else. The Ummah’s acceptance of the two Sahihs is only proof that we do not need to check the authenticity of their reports before acting upon them. This is unlike narrations found in other books, which need to be scrutinized and authenticated first. But just because the Ummah has agreed to act upon those narrations, doesn’t mean that they have agreed that the narrations are decisively the words of the Prophet ﷺ.
Comment: and the claim that there is consensus with regards to the authenticity of all reports in the two Sahihs, is a claim that should be subjected to further study.