Therefore...

Therefore, in the light of this, we must first define the roots and then the branches according to the way of the people of truth and reality; thereafter, we must investigate how they are both applied and define the pillars or the foundation of knowledge and action; we must then explain how they are both contained in the three above‑mentioned levels.

An Investigation of the Roots ** ** An Investigation of the Roots: according to the way of the people of truth Know that there are great differences of opinion concerning this matter: some believe that the roots of faith are two in number, that is, affirmation of Allah and His Prophet and certainty of belief with regard to the laws (and the fact that the Prophet ruled by these laws), while the people known as the Ash'arites withhold affirmation of that about which there is disagreement and ambiguity.

According to others, the roots of the faith are three in number: affirmation with the heart, the manifestation of this belief on the tongue, and the actions of the limbs ‑ and this opinion is shared by some of the Shi'ahs. The Shi'ahs say that the roots of the faith are three in number: affirmation of the Oneness of Allah in His Essence and justice of His actions, affirmation of the prophethood of all the prophets, and the im­amate: of the infallible Imams.

Other Shi'ahs believe that the number of (the roots of the faith are four in number: divine unity, divine justice, prophethood and imamate. According to the Mu'tazalites, the roots of the faith are five in number: divine unity, divine justice, affirmation of prophethood, the promised reward and retribution, and the enjoining of good and the forbid­ding of evil.

Some of the later Shi'ahs also believe this, although they express their belief in (slightly) different terms, namely that the roots of belief are five in number: divine unity, divine justice, prophethood, imamate and al‑ma`ad, the resurrection and return of man to his Creator to face judgment. This is in fact the correct system of belief it is what I prefer and what is preferred by most of the scholars of the people of Allah.

The one who possesses a correct system of belief and perfect faith must also believe in the unity of Allah so that he may free himself from associating others (or other things) with Allah.