Ahmad bin Hanbal was born in Baghdad, in the year 780 CE. Of pure Arab lineage, Ibn Hanbal belonged to the tribe of Shaybaan through both parents. He was still an infant when his father died at the age of 30. When Ibn Hanbal was fifteen, he began to study the Traditions (Ahadeeth) of the Prophet Muhammad, , (may Allah exalt his mention). Seeking to learn from the great scholars of his day, he traveled to the cities of Koofah and Basrah in Iraq; Makkah, Hijaaz and Al-Madeenah in Arabia; and to the lands of Yemen and Syria. He made five pilgrimages to Makkah, three of which were on foot. Ibn Hanbal led a life of asceticism and humility, acquiring many students. He had eight children, of whom two were well known and closely associated with his intellectual work: Saalih (died 880 CE) and ‘Abdullaah (died 903 CE).

Ahmad bin Hanbal became so competent in the sciences of religion that al-Imaam Ash-Shaafi’ee said: “I left Baghdad and did not leave there any man more knowledgeable than Ibn Hanbal.”

At the risk of his life, Ibn Hanbal refused to subscribe to the Mu’tazilee doctrine. He was put in chains, beaten and imprisoned for more than two years. After his release, he did not resume his lectures until the inquisition was publicly proclaimed at an end. In order to survive the ordeal, some scholars had recanted, and later claimed the privilege of dissimulation, Taqiyyah (hiding their feelings because of the extreme danger involved), as a justification for their behavior. Other scholars, following the example of Ibn Hanbal refused to renounce their beliefs.

In 833 CE, Ibn Hanbal and another scholar, Muhammad bin Nooh, may Allah have mercy on him, who had also refused to recant, were cited to appear for trial before Caliph al-Ma’moon, who was in Tarsus (now in modern Turkey) at the time. They were sent off in chains from Baghdad; but shortly after beginning their journey, the Caliph died and on their trip back to the capital, Ibn Nooh died as well.

Ibn Hanbal was ordered to appear before the new Caliph, al-Mu’tasim. He was on trial for three days, and on the third day after the learned men disputed with him, there followed a private conference with the Caliph who asked Ibn Hanbal to yield at least a little so that he might grant him his freedom. Ibn Hanbal made the same reply he had been making from the beginning of the inquisition; he would yield when given some proof for modifying his faith derived from the Quran and the Traditions of Prophet Muhammad, . Losing patience, the Caliph ordered that he be taken away and lashed. Throughout the lashing, the Caliph persisted in his attempts to obtain a recantation, but to no avail. Ibn Hanbal's unflinching spirit affected the Caliph, but his advisers warned that if he discontinued the punishment, he would be accused of having opposed the doctrine of his predecessor al-Ma’moon, and it would be counted as a victory for Ibn Hanbal resulting in dire consequences on the reign of the caliphs. Nevertheless, the Caliph's treatment of Ibn Hanbal had to be suspended, because of the mounting anger of the populace gathering outside the palace and preparing to attack it. Ibn Hanbal is reported to have been beaten by 150 lashers, each in turn striking him twice and moving aside. The scars from his wounds remained with him to the end of his life.

Ibn Hanbal earned the greatest reputation of all the persons involved in the inquisition and the everlasting gratitude of the Muslim people. He is credited with having held his ground in the face of all odds, saving Muslims from becoming unbelievers. Ibn Hanbal’s record in history is that of a great scholar who stood firm in the face of the Mu’tazilites’ heresies, and their campaign to alter Allah’s religion.

Ibn Hanbal died in 855 CE, in Baghdad. He was then 77 years old. People attending his funeral ceremony flooded the streets of Baghdad and the procession was estimated at more than 800,000 mourners.