without conviction in the heart is the speech of hypocrites, and this is only called “words” with a qualification, as Allah Most High says:

“They say with their tongues what is not in their hearts.”

Likewise, actions of the limbs without actions of the heart are among the deeds of hypocrites, which Allah does not accept.

Thus, the formulation used by the early generations encompasses both inward and outward words and deeds. However, since some people might not understand that intention is included, some of them added: “And intention.” Others then explained that words, deeds, and intention are not accepted merely as such, but must conform to the Sunnah. This, too, is true. Those who said “words and deeds” intended to explain that faith encompasses these categories, not to specify the qualities those words and deeds must possess.

Likewise, whoever said, “Conviction of the heart, speech of the tongue, and action of the limbs,” used “speech” and “action” to designate outward manifestations, and therefore needed to add conviction of the heart. By “conviction of the heart,” he must also include the actions of the heart that accompany its affirmation of the truth, such as love of Allah, fear of Allah, reliance upon Allah, and the like. For the actions of the heart have an even stronger claim to inclusion in faith than the actions of the limbs, by agreement of all groups.

Some jurists of the generation following the Successors did not agree to describe faith as decreasing, because they found increase mentioned in the Quran but did not find decrease mentioned. This is one of the two views reported from Mālik. The other report from him—which is the well-known position among his followers—agrees with the position of the rest: that faith increases and decreases.

Some avoided the terms “increase” and “decrease” in favour of speaking of differences in degree, saying: “I say that faith differs in degree and varies.” This is reported from Ibn al-Mubārak.