Second: The first book compiled exclusively of sound (ṣaḥīḥ) narrations is Ṣaḥīḥ al-Bukhārī, followed by Ṣaḥīḥ Muslim. After the Qur’an, these are the most reliable books in Islam. Al-Bukhārī’s collection is the more rigorous and the richer in benefits—though some have claimed that Muslim’s is more authentic, the correct view is the first. Muslim’s distinct merit lies in gathering all the various chains of a given ḥadīth in a single place.

Neither of the two authors intended to gather every sound narration, nor did they claim to. Some have alleged that only a handful of authentic reports escaped them, but this has been rejected. The sound position is that only a small number of narrations found in the “five foundational works” were missed—namely, the two Ṣaḥīḥs together with the Sunan of Abū Dāwūd, al-Tirmidhī, and al-Nasāʾī.

The total number of narrations in al-Bukhārī is 7,275 with repetitions; without repetitions it is about 4,000. Muslim, after omitting repetitions, likewise contains roughly 4,000. Additional sound material is to be identified in the relied-upon Sunan collections—such as the Sunan of Abū Dāwūd, al-Tirmidhī, al-Nasāʾī, Ibn Khuzaymah, al-Dāraqutnī, al-Ḥākim, al-Bayhaqī, and others—when those narrations are explicitly judged sound. Mere inclusion in these works is not sufficient unless the book’s author expressly limited himself to authentic reports. Al-Ḥākim devoted special attention to recording what is not found in the two Ṣaḥīḥs, yet he is lenient; therefore, whatever he declared sound but did not