The benefit of [the existence of] this difference is that the one who is devoid of actions and commits the forbidden acts, will not have the name of ‘believer’ applied to him absolutely and it is said in this regard that he is deficient in faith, since he has neglected some parts of it. And in the view of those (i.e. the Ash’aris) the name of ‘believer’ can be applied to him absolutely because [in their view] Imaan signifies assent, tasdiq and such a person has fulfilled this.

Our evidence for this is the saying of the Exalted:

Verily the Believers are those whose hearts tremble when Allaah is mentioned… (Anfal 8:2)

Up to His statement:

…they are the Believers in truth. (Anfal 8:4)

So he described them with the real and true Imaan due the presence of these actions. And the Most High said:

And never would Allaah cause your Imaan to be lost (Baqarah 2:143)

Meaning, your prayer. So he applied the term Imaan to the prayer, yet it is an action.

What also gives evidence to this is what is reported from Abu Hurairah – may Allaah be pleased with him – that he said, "The Messenger of Allaah (sallallaahu alaihi wasallam) said: Imaan consists of seventy odd branches" and in another narration, "sixty odd branches: the most superior of them being the declaration that there is none worthy of worship except Allaah and the lowest of them being the removal of something harmful from the path. And modesty is a branch of Imaan"

[What also constitutes our evidence is that] the one who is compelled into Imaan, his entrance into Imaan is correct and acceptable. Because if Imaan was something unique to the heart [alone], his entry into Imaan would not have been correct, since that is not possible with compulsion. It can be attained from the perspective of the outward sayings and deeds. And because Imaan is actually what constitutes the deen (religion) of a Muslim, and the deen is a term that signifies acts of obedience, then likewise [is] the Imaan that is characteristic of him. And also [the fact that] the term ‘perfect in faith’ cannot be applied to the one who abandons fasting, zakaah, and who commits the obscene acts.

Issue: [Increase and Decrease in Imaan]

And it is possible for Imaan to increase and decrease. Its increase is by performance of the acts of obedience and its decrease is by abandoning them and doing acts of disobedience. This is in opposition to the one who says that Imaan is [merely] the knowledge of the heart and its assent and that these two are indicatives, and that increase and decrease cannot take place in the case of indicative matters.

And it is reported from Ibn Abbaas, Abu Hurairah and Abu ad-Dardaa – may Allaah be pleased with them, "Imaan increases and decreases". So when he neglects some of it and performs the forbidden acts then he has neglected some of the actions of Imaan. Hence, it is permitted that Imaan be described with increase and decrease.

Issue: [Is the Imaan of the Mukallifeen Equal?]

And the Imaan of all those tasked (with obedience) from amongst the Angels, Prophets - and those besides them such as the Martyrs and Truthful ones – is not equal. Rather they excel one another to the extent of their level in performing acts of obedience. This is in opposition to the one who says that Imaan is [merely] the assent, tasdiq, of the heart and that superiority only takes place with respect to knowledge and the variety in its evidences! And we have already mentioned that acts of obedience are from Imaan. It is also known that people excel each other in the acts of obedience. So some of them increase over others, hence it is necessary that superiority be acquired with respect to it.

Issue: [The Difference Between Islaam and Imaan]

And Imaan and Islaam are two terms referring to two [distinct] meanings. Islaam is a term that refers to the two Shahadahs (testimonies of belief) and assent, tasdiq, of the heart. And Imaan is a term that signifies all of the acts of obedience. This is in opposition to the one who says that Islaam and Imaan are the same.

And the evidence for the difference between them is the statement of the Most High:

Verily the Muslims, men and women, the Believers men and women… (Ahzab 33:36)

So he placed Imaan after Islaam (next to it) and something is not placed straight after itself. So it is known from this that Imaan has a meaning which extends that of Islaam.