Martyrdom

Toward the end of his life the Imam was subjected to severe restrictions placed upon him by the Abbasid caliph Mansur, who ordered such torture and merciless killing of many of the descendants of the Prophet who were Shi'ite that his actions even surpassed the cruelty and heedlessness of the Umayyads.

At his order they were arrested in groups, some thrown into deep and dark prisons and tortured until they died, while others were beheaded or buried alive or placed at the base of or between walls of buildings, and walls were constructed over them. Hisham, the Umayyad caliph, had ordered the sixth Imam to be arrested and brought to Damascus. Later, the Imam was arrested by Saffah, the Abbasid caliph, and brought to Iraq.

Finally, Mansur had him arrested again and brought to Samarrah where he had the Imam kept under supervision, was in every way harsh and discourteous to him, and several times thought of killing him. Eventually the Imam was allowed to return to Medina where he spent the rest of his life in hiding, until he was poisoned and martyred through the intrigue of Mansur.

Upon hearing the news of the Imam's martyrdom, Mansur wrote to the governor of Medina instructing him to go to the house of the Imam on the pretext of expressing his condolences to the family, to ask for the Imam's will and testament and read it. Whoever was chosen by the Imam as his inheritor and successor should be beheaded on the spot.

Of course the aim of Mansur was to put an end to the whole question of the imamate and to Shi'ite aspirations. When the governor of Medina, following orders, read the last will and testament, he saw that the Imam had chosen four people rather than one to administer his last will and testament: the caliph himself, the governor of Medina, 'Abdullah Aftah, the Imam's older son, and Musa, his younger son. In this way the plot of Mansur failed.