Sahih Muslim () is a 9th-century hadith collection and a book of sunnah compiled by the Persian scholar Muslim ibn al-Ḥajjāj (815–875). It is one of the most valued books in Sunni Islam after the Quran, alongside Sahih al-Bukhari. Sahih Muslim is also one of the Kutub al-Sittah, the six major Sunni collections of hadith of the Islamic prophet Muhammad. The book is also revered by Zaydi Shias. It consists of approximately 7,500 hadith narrations across its introduction and 56 books. Content Sahih Muslim contains approximately 5,500 - 7,500 hadith narrations in its introduction and 56 books. Kâtip Çelebi (d. 1657) and Siddiq Hasan Khan (d. 1890) both counted 7,275 narrations. Muhammad Fuad Abdul Baqi wrote that there are 3,033 narrations without considering repetitions. Mashhur ibn Hasan Al Salman, a student of Al-Albani (d. 1999), built upon this number, counting 7,385 total narrations, which, combined with the ten in the introduction, add up to a total of 7,395. Muslim wrote an introduction to his collection of hadith, wherein he clarified the reasoning behind choosing the hadith he chose to include in his Sahih. Development According to Al-Khatib al-Baghdadi, Muslim began writing the Sahih for Ahmad ibn Salamah an-Naysaburi. He was also compelled to write the Sahih for what he observed to be the poor character of his contemporary hadith scholars, and their lack of reluctance to spread daʻīf (weak) narrations. Muslim collected 300,000 narrations and chose 4,000 to be included in his book. He divided narrators of hadith into three tiers based on their memory and character: those who possessed authentic memory and were of perfect character, honest and trustworthy. those of slightly weaker memory and perfection, trustworthy, knowledgeable and honest. those whose honesty was disputed or was a subject of discussion. Muslim did not include hadith which were narrated by those who belonged to the last tier. Moreover, Muslim only recorded hadith that were narrated to him by an unbroken isnad (chain) of narrators through two reliable tabi'un, each of which had to be narrated through two companions of Muhammad. Reception Sunni Muslims regard Sahih Muslim as the second most important book of the Kutub al-Sittah. Sahih Muslim and Sahih al-Bukhari are together referred to as the 'Sahihayn (The Two Sahihs)'. In the Introduction to the Science of Hadith, Ibn al-Salah wrote: "The first to author a Sahih was Bukhari [...], followed by Abū al-Ḥusayn Muslim ibn al-Ḥajjāj an-Naysābūrī