The Usul al-kafi is part of the Kitab al-kafi, a multivolume collection of over sixteen thousand Hadith that were compiled between 921 and 940 by Abu Ja’far Muhammad ibn Ya’qub ibn Ishaq al-Kulayni al-Razi (known as al-Kulayni) in the city of Baghdad. Hadith are the sayings of the prophet Muhammad (the founder of Islam, born in 570) and, in some instances, the sayings of those Shia imams believed by the Shia to be direct successors to Muhammad.
The Sunni and Shia branches of Islam have separate collections of Hadith. The primary difference between the two is that whereas Sunni Hadith focus on the person of Muhammad, Shia Hadith—from a Shia sect known as the Twelvers—focus on the sayings of Muhammad and the twelve imams who followed him. The Twelvers, also known as the Ithna ‘Ashariyya, are the largest Shia sect and are the dominant sect in modern-day Iran.
It is important to distinguish between the Hadith and the Qur'an. Most Muslims believe that the Qur'an is the literal...
Page of the Qur’an (Yale University Art Gallery)View Full Size