al- Mufid studied with him when as-Saduq was in Baghdad...

al- Mufid studied with him when as-Saduq was in Baghdad, and heard Traditions from him. He received his authorization (ijazah) to transmit his writings and his narrations of Traditions; thus as- Saduq was one of al-Mufid's mentors in Traditions. I believe that the duration of this relationship was short for the following reason. As-Saduq was born and raised in Qum and then emigrated to Rayy, where he resided until he died.

He travelled in search of Traditions and other material, and made a journey to Iraq on his way to the hajj. As-Saduq himself mentions that he came to Baghdad on his way to the hajj in the year 352/963.[^10] It appears that he came to Baghdad towards the end of that year, because he left Rayy on a pilgrimage to Mashhad (of ar-Rida, peace be upon him) in the middle of that year.[^11] His hajj was…