All Shia Four Books

The Four Books, al-Kutub al-Arba'a, is the canonical grouping of four hadith collections that Twelver Shia Islam treats as its principal corpus of prophetic and Imami tradition. Compiled in the ninth and tenth centuries by three scholars who shared the given name Muhammad and are collectively remembered as the Three Muhammads, Shaykh al-Kulayni, Shaykh al-Saduq and Shaykh al-Tusi, the four works are Kitab al-Kafi, Man La Yahduruhu al-Faqih, Tahdhib al-Ahkam and al-Istibsar, listed here in the order of their composition. Kitab al-Kafi, al-Kulayni's collection, is regarded as the most important and authoritative of the four, and Shaykh al-Tusi alone compiled the last two, Tahdhib al-Ahkam and al-Istibsar, as companion legal works. The Four Books drew together a much larger body of earlier hadith literature, the four hundred foundational texts called usul that Shia Muslims had used to transmit reports from the companions of the Twelve Imams before this canon consolidated it. Together the four works remain the primary sources cited in Twelver Shia theology, jurisprudence and religious practice.