Imam (A) was brought up under the care of his father for 20 years. After the death of his father, he took over the responsibility of Imamat and guided the people from Madina.

At the time of the death of Imam Ja'far as-Sadiq (A), some of the Shia claimed that Isma'il, his eldest son, was the Imam. This view was incorrect because Isma'il had died during the life time of his father (A) and moreover, it was against the specific instructions of the sixth Imam (A).

Imam (A) lived during the time of four Bani Abbas Caliphs, Mansoor, Mahdi, Hadi and Haroon Rashid. Although he was allowed some freedom in the beginning, it was not long before the attention of the rulers was turned on him.

When Haroon came to power in 170 A.H., he set about killing the descendants of Imam Ali (A). At first, however, he allowed Imam (A) to continue guiding the people.

Ali bin Yaqtin was the prime minister of Haroon. Unknown to Haroon, he was a Shia and followed the rulings of Imam (A). He also used to try to help the Shia secretly by using his powerful influence.

One day Haroon sent him some robes as a gift for his services. Amongst them was a costly black woollen cloak with a gold design. Ali bin Yaqtin sent the robes to Imam (A) as a gift, together with some money for Khums.

Imam (A) accepted the money and the robes, but returned the cloak with a letter saying, "Keep the cloak and do not let it leave your hands. An event will occur when you will need it."

Although Ali was disappointed that his gift had been returned, he followed Imam's (A) instructions.

Some time later, one of the servants of Ali bin Yaqtin left his service after a quarrel. He went to report to Haroon that Ali was a secret follower of Imam (A). He also told Haroon how he had sent the cloak as a gift to Imam (A) together with money.

Haroon was furious and summoned Ali bin Yaqtin at once, demanding to see the cloak. Because of Imam's (A) advice the cloak was still in his possession and he brought it at once. Haroon was ashamed at doubting his prime minister and ordered that the servant be flogged with a thousand lashes.

Haroon began to resent the popularity and power that Imam (A) had over the Muslims. Once when Haroon went over to Madina, he approached the tomb of the Holy Prophet (S) and said, "Greetings to you, O Prophet of Allah, greetings to you, my cousin." He was trying to show the people that he was related to the Holy Prophet (S) because he was a descendant of Abbas, the brother of Abdullah. Imam (A) also approached the tomb and said, "Greetings to you, O Prophet of Allah, greetings to you, my father." Imam (A) was proving to the people and Haroon that he was a direct descendant of the Holy Prophet (S). When he heard this, Haroon's face went red in anger.

In Baghdad, information continued to reach Haroon about the growing popularity of Imam (A) and he felt threatened. In spite of the fact that Imam (A) had not criticised the government, he had him handcuffed and brought to Basra from Madina. In Basra, Imam (A) was imprisoned for one year under the care of Isa bin Ja'far. He was then moved to a prison in Baghdad, and then moved to different prisons. He was finally kept under the guard of Sindi bin Shahik. The accursed Sindi eventually killed Imam (A) by presenting him with poisoned dates. Imam (A) immediately felt the effect of the poison, and after three days of fever, he left this world.

Sindi put the body of Imam (A) on a bridge in Baghdad and invited the people to come and see the body and prove to themselves that he had not been killed by force, but had died naturally.

Imam (A) died on 6th Safar 183 A.H. after being the guide for the people for 35 years. He was buried in Kazmain, near Baghdad. The Ghusl and Kafan was performed by his son Imam Ali ar-Riza (A), who also led his funeral prayers.