ʿUyūn akhbār al-Riḍā 1, narration 93

Translation

7-14 Abu Bakr Muhammad ibn Ali ibn Muhammad ibn Hatam narrated that Abdullah ibn Bahr ash-Shaybani quoted on the authority of al-Khazri Abul Abbas in Kufa, on the authority of al-Thowbani, “The common practice of Abil Hassan Musa ibn Ja’far for ten years (during his period of imprisonment) was to fall into prostration from after sunrise until noon. Sometimes Harun went to the roof of the building which overlooked the prison and saw Abul Hassan (s) while he was prostrating. He asked al-Rabee’, “O Rabee’! What is this attire which I see here everyday in this place?” I said, “O Commander of the Faithful! This is not just some attire. It is Musa ibn Ja’far (s) who prostrates every day from sunrise until noon.” Al-Rabee’ said, “Harun told me, ‘He is one of the monastic members of the Hashemites.’ I said, ‘Then why do you treat him with such harshness in prison?’ Harun said, ‘I wish it wasn’t so! I have no other choice.’”

Translation: Dr. Ali Peiravi — published with the edition, reproduced verbatim.