Everything in this book that is narrated from Bukayr ibn A'yun has been transmitted by me from my father - may Allah {SWT} be pleased with him - from Ali ibn Ibrahim, from his father, from Muhammad ibn Abi 'Umayr, from Bukayr ibn A'yun. He was a Kufan, known by the kunya Abu Al-Juhm, and was a freed servant (mawla) of Banu Shayban. When Imam Jafar ibn Muhammad Al-Sadiq {a.s} was informed of the death of Bukayr ibn A'yun, he said: "By Allah {SWT}, indeed Allah {SWT}, the Almighty and Glorious, has placed him between His Messenger and the Commander of the Faithful, peace and blessings be upon them both."