Calling to Allah is obligatory upon those who follow the Messenger, may Allah bless him and grant him peace, namely his community. Allah has described them in these terms, as in His words, Most High:

“Those who follow the Messenger, the unlettered Prophet,”

through to His words:

“the successful.”

This passage concerns him, may Allah bless him and grant him peace. Concerning them, Allah says:

“You are the best community brought forth for mankind”—the verse.

And He says:

“The believing men and believing women are allies of one another; they enjoin what is right and forbid what is wrong”—the verse.

This duty rests upon the community as a whole. It is a collective obligation: when some fulfil it, the others are relieved of it. As Allah says:

“Let there be among you a group calling to goodness”—the verse.

Thus, the community collectively takes his place in calling to Allah. On this basis, their consensus constitutes authoritative proof. When they disagree about anything, they refer it back to Allah and His Messenger.

With this established, every believer must love what Allah and His Messenger love and hate what Allah and His Messenger hate, as indicated in His Book. No one may make anyone other than the Messenger of Allah, may Allah bless him and grant him peace, the foundational authority in religion, nor make religious pronouncements except on the basis of the Book of Allah, Mighty and Majestic.

Whoever sets up an individual—whoever he may be—and bases allegiance and hostility on agreement with him in word and deed is

“among those who divided their religion and became sects”—the verse.

If a man acquires religious understanding and cultivates his conduct according to the way of a group of believers—for example, by following imams and shaykhs—he may not make his exemplar and his companions the standard, showing allegiance to those who agree with them