and to establish prayer, give zakat, fast Ramadan, and perform pilgrimage to the House.” In a hadith in al-Musnad, he said:

“Islam is outward, while faith is in the heart.”

The foundation of faith lies in the heart and consists of the heart’s affirmation and action—its acknowledgment through assent, love, and submission. Whatever is in the heart must manifest its necessary effects and implications in the limbs. If a person does not act accordingly, this indicates its absence or weakness. Thus, outward deeds are among the necessary effects and implications of the heart’s faith. They confirm, indicate, and bear witness to what is in the heart. They are a branch and a constituent part of faith considered in its entirety. Yet what is in the heart is the foundation of what the limbs do. As Abū Hurayrah—may Allah be pleased with him—said:

“The heart is a king, and the limbs are its soldiers. If the king is good, its soldiers are good; if the king is corrupt, its soldiers are corrupt.”

In the two Sahīh collections, the Prophet—may Allah bless him and grant him peace—is reported to have said:

“Indeed, there is a piece of flesh in the body: when it is sound, the rest of the body is sound because of it; and when it is corrupt, the rest of the body is corrupt because of it. Indeed, it is the heart.”

For this reason, some groups thought that faith resides exclusively in the heart, and that the deeds of the limbs do not fall within its meaning, but are merely its fruits and consequences, which indicate its presence. Their extremists—such as Jahm and his followers—went so far as to say that a person may believe in his heart while uttering nothing but words of disbelief, despite being capable of making an outward profession, and that what is in his heart would nevertheless constitute faith that benefits him in the Hereafter. They also said that whenever the Lawgiver judges someone to be a disbeliever on account of a deed or statement, it is because that deed or statement indicates the absence of what is in the heart.

Their position is contradictory. If that is evidence necessarily entailing the absence of faith from the heart, then it is impossible for faith to be present in