Muhammad ibn Ali ibn al-Husayn al-Qummi,ash-ShaykhAbu Jafar Ibn Babawayh (or Babuyah)as-Saduq (c.306/919-381/991), lived in Rayy wherehe died and was buried. His tomb is still there, and visitedby crowds of people, in what is known as the Ibn Baba-wayh Cemetery" in a southern suburb of Tehran.Shaykh at -Taifah (The Leader of the Shi`ites) at-Tusi-Abu Jafar Muhammad ibn al-Hasan (385/995 - 460/1076), an-Najashi - Abu l-`Abbas Ahmad ibn Ali (372/982 - 450/1058), al-`Allamah al-Hilli - Jamalu d-Dinal-Hasan ibn Yusuf ibn al-Mutahhar (648/1250 - 726/1325) and others who studied with, and learnt from, them,said about him: He was of the first rank, had a good memory, was knowledge able in fiqh and had memorized hadith.Hislike was not seen among (the men ofhadithof) the people of Qum as regards his memory and great knowledge.He was our leader, our jurist and the symbol of our sect in Khurasan (and the East). He came to Baghdad in 355(966), and the leading scholars of the sect heard (tradi-tions) from him. If he is compared with those who heard traditions from him, they were older than him, had been hearing traditions before he had, and had precedence over him in the order of chains of transmission. He wrote about three hundred works. During his work he wrote his famous book named as Khasal.