The Shi'as have another "rukn" thus bringing the total to five principles.

The Shi'as have another "rukn" thus bringing the total to five principles. This fifth pillar is faith in the imamate. According to the Shi'a point of view, the Imamate, like Prophethood, is divine vicegerency. Just as it is God Almighty Who chose one from amongst His servants for the rank of Prophethood or Messengership, in the same way it is God Who chooses the Imams.

God Almighty Himself commanded His Prophet to announce the Imamate (spiritual leadership) of the selected person before his death. The Prophet, according to divine command, chose a leader for mankind to protect and complete the religious code. The only difference between a Prophet and an Imam is that the Prophet receives "wahy" (revelation) from God, while the Imam, through a special blessing, receives commands from the prophet.

So the prophet is the messenger of God and the Imam is the messenger of the Prophet. The Imamate comprises twelve perfect persons, and every Imam appoints his successor by a specific indication (nass). Like all Prophets, the Imams are also infallible; there is no possibility of their committing any sin. The infallibility of the Imam is clearly proved from what God Almighty says in the Holy Quran: "Verily, I make you an Imam for mankind.

He (Abraham) said: "And of my offspring?" He said: "My covenant does not reach to the unjust." Moreover, an Imam is superior to all men in all matters of knowledge and character, since the very purpose of the Imamate is that humanity may be exalted to the highest stage and may be adorned with knowledge and good actions through the imitation of the Imam.

What has been said in the Holy Quran about Prophethood (that the Prophets have been sent to people as His signs, to teach them the Book and Wisdom), is equally applicable to an Imam too, because an imperfect person cannot make mother person perfect. What can someone give to another, when he does not possess anything himself? A misguided man cannot guide another man. Judged accordingly, an Imam is a little below the Prophet, but over every human being.

Anyone who believes in the Imam is called, according to the Shi'a terminology, a "mu'min" (a man of faith and trust) in the special sense. Anyone who acknowledges the four fundamentals, which are the centre of faith of all the Muslims, is called a "Muslim" and a "mu'min" in a general sense; as has been said earlier, all Islamic laws apply to him: the protection of his life, property, respect and honour is obligatory.