Abu Abdullah Hussain bin Ali was born on the 3rd Shaban, 4/January, 626 in Medina. When the news of his birth reached to Muhammad, he came to his daughter's house, and took the newly-born child in his arms affectionately, and named him Hussain. He spent his early life in the godly lap of Muhammad, who loved him too much. Among the numerous sayings of Muhammad concerning Hussain is the one to this effect that, "I owe my being to Hussain, and Hussain owes his being to me." (Ibn Majah, 1st vol., p. 33). It is further related that once, while sermoning in the mosque, Muhammad was interrupted all of a sudden by the cry of a boy, whose voice resembled that of Hussain. He asked to a person to enquire whether Hussain was weeping. Muhammad was soon reported that the weeping boy was a student, whose teacher had punished him due to negligence to his lesson. Muhammad sent for the teacher and said, "Please do not punish this boy so much that causes him to weep, as his voice resembles that of my child Hussain."
Hussain was 6 years old during the demise of Muhammad and his mother. He was married to Shahr Banu, the daughter of Yazdigard, the last Sassanid king of Iran.
Hussain's self-control and patience must indeed have been remarkable, for once when a slave-girl spilled a dish of thick soup all over the Imam's head and neck, he refrained from reprimanding her, but on the contrary, he graciously gave her freedom.
The sources acknowledge in the face of the facts that Hussain was the superlative genius of his age in learning and knowledge. "The traditions indicating his profound knowledge," writes Abdullah al-Alaili, "are more than one can count. There were many complicated cases in which his judgement were astonishing even to the learned and distinguished scholars, till Abdullah bin Umar commented that Hussain was the source of inspiration of knowledge." During his living in Medina, since the death of his father, Hussain was mostly engaged in the intellectual pursuits with his followers. It infers from the collection of his saying, as recorded by Kulaini (d. 329/941) in his "Usul al-Kafi" that Hussain highly stressed on the application of intellect in religion. For instance, his few saying to this effect are given below:-
* Intellect is a guide to every believer. ("al-Kafi", p. 60)
* The lack of intellect and faith in no case can be overlooked and forgiven. Being without faith and religion is equal to being without peace and security. (Ibid. p. 64)
* A person devoid of intellect cannot be conceived except as a corpse. (Ibid.)
* One who has intellect has a faith. And he who has faith has a peace in paradise. (Ibid. p. 27)
* The reasoning potentiality is the chief pillar of human existence. It is a fountain spring of sagacity, comprehension, memory and knowledge. It is through reason one knows who guides him and who misguides him. (Ibid. p. 60)