Baqir is a derivate of the word "Baqara" which means to open up or to expand. Imam Muhammad Baqir (AS) was named as such since he introduced and spread the knowledge and teachings of various dimensions and implemented the knowledge streams in a manner which had never been seen earlier. Imam Muhammad Baqir (AS), like the other Imams, in knowledge and science had no equal. Great learned men benefited from his knowledge and science and used to seek help from him to solve their problems.
Imam Muhammad Baqir (AS) was about two and a half years old when he had to accompany Imam Hussein (AS) and the rest of his family members on the journey to Karbala. After the tiring journey from Medina to Karbala, he witnessed the shocking and tragic events of Karbala and then the heart-rupturing events in Syria and Iraq. After one year of detention in Damascus he returned in 62 AH to Medina when he was only four.
During the Imamate of Imam Baqir (AS), as a result of the injustice of the Umayyads, revolts and wars broke out in some corners of the Islamic world every day. Moreover, there were disputes within the Umayyad family itself which kept the caliphate busy and to a certain extent left the members of the Household of the Prophet (pbuh) alone. From the other side, the tragedy of Karbala and the oppression suffered by the Household of the Prophet (pbuh), of which the Fourth Imam was the most noteworthy embodiment, had attracted many Muslims to the Imam. These factors combined to make it possible for people and especially the Shiites to go in great numbers to Medina and to come into the presence of the Imam. Possibilities for disseminating the truth about Islam and the sciences of the Household of the Prophet (pbuh), which had never existed for the Imams before him, were presented by Imam Baqir (AS). The proof of this fact is the innumerable traditions recounted from the Fifth Imam and the large number of illustrious men of science and Shiite scholars who were trained by him in different Islamic sciences. These names are listed in books of biographies of famous men in Islam.
In 100 AH, Hasham bin Abdul Malik became the caliph. He was a known enemy of the Ahl al-Bayt (pbuh) and he did not waste any opportunity to bring hardship to the Ahl al-Bayt (pbuh). Allame Majlisi writes that during the last days of his caliphate, Hasham came to Mecca for Hajj. Imam Muhammad Baqir (AS) and his son Imam Jafar Sadiq (AS) were also present. Hasham was furious about the popularity of the Imams. Upon his return to Damascus, he ordered the governor of Medina, Ibrahim bin Walid to send the two Imams (AS) to his court. Hasham had planned to malign the Imams in his court but the Imams (AS) overturned his plans which further ignited his enmity and he ordered the Imams (AS) to be jailed. While in the jail, Imam Muhammad Baqir (AS) gave sermons to other prisoners which created an atmosphere of great enthusiasm and devotion towards the Imam (AS) and against Hasham.
In his life of respectable and scholarly retirement in Medina, the Imam was frequently called upon to explain particular teachings in regard to Imamate. A synopsis of his teaching in the Ma’athirul-Baqir is given in Cannon Sell’s Ithna Ashariya, an interesting part of which may well be quoted, as it shows the emphasis at this early period on the intellectual and spiritual character of the Imamate.
The caliph then ordered the governor of Medina to poison the Imam since he was becoming a constant threat. The governor of Medina - Ibrahim bin Walid carried out the orders and poisoned the Imam (AS) in 114 AH.
This took place on the seventh day of the month of Zil-Hajjah, in Medina. His body was buried in Baqi’ cemetery alongside the graves of Imam Hassan (AS) and Imam Sajjad (AS) in Medina.