The son of Imam Muhammad al-Baqir, son of al-Imam Zain al-'Abidin, son of al-Husayn, son of Ali bin Abi Talib (r), Ja'far was born on the eighth of Ramadan in the year 83 H. His mother was the daughter of al-Qassim (r), whose great grandfather was Abu Bakr as-Siddiq (r).
Ja'far narrated from his father, Muhammad al-Baqir, that a man came to his grandfather, Zain al-'Abidin, and said, "Tell me about Abu Bakr!" He said, "You mean as-Siddiq?" The man said, "How do you call him as-Siddiq when he is against you, the Family of the Prophet (s)?" He replied, "Woe to you. The Prophet (s) called him as-Siddiq, and Allah accepted his title of as-Siddiq. If you want to come to me, keep the love of Abu Bakr and 'Umar in your heart."
He took the knowledge of hadith from two sources: from his father through 'Ali (r) and from his maternal grandfather al-Qassim. The two Sufyans, Sufyan ath-Thawri and Sufyan bin Ayinah, Imam Malik, Imam Abu Hanifa, and al-Qattan all narrated hadith through him, as did many others from later hadith scholars. He was a mufassir al-Qur'an or master in exegesis, a scholar of jurisprudence, and one of the greatest mujtahids (qualified to give legal decisions) in Madinah. Ja'far (r) acquired both the external religious knowledge as well as the internal confirmation of its reality in the heart. The latter was reflected in his many visions and miraculous powers, too numerous to tell.
From his knowledge he used to say to Sufyan ath-Thawri, "If Allah bestows on you a favor, and you wish to keep that favor, then you must praise and thank Him excessively, because He said, "If you are thankful Allah will increase for you" [14:7]. He also said, "If the door of provision is closed for you, then make a great deal of istighfaar (begging forgiveness), because Allah said, "Seek forgiveness of your Lord, certainly Your Lord is oft-Forgiving" [11:52]. And he said to Sufyan, "If you are upset by the tyranny of a Sultan or other oppression that you witness, say "There is no change and no power except with Allah," because it is the key to Relief and one of the Treasures of Paradise."
He received from the Prophet (s) two lines of inheritance: the secret of the Prophet (s) through 'Ali (r) and the secret of the Prophet (s) through Abu Bakr (r). In him the two lineages met and for that reason he was called "The Inheritor of the Prophetic Station (Maqam an-Nubuwwa) and the Inheritor of the Truthful Station (Maqam as-siddiqiyya)." In him was reflected the light of the knowledge of Truth and Reality. That light shone forth and that knowledge was spread widely through him during his lifetime.
He spent his life in worship and acts of piety for the sake of Allah. He rejected all positions of fame in favor of cuzla or isolation from the lower world. One of his contemporaries, cUmar ibn Abi-l- Muqdam, said, "When I look at Ja'far bin Muhammad I see the lineage and the secret of the Prophet Muhammad (s) united in him."
Imam Ja'far (RAA) passed away in 148 H. and was buried in Jannat al-Baqi in the same grave as that of his father, Muhammad al-Baqir, his grandfather, Zain al-'Abidin, and the uncle of his grandfather, al-Hasan ibn 'Ali (r).
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