follows the Messenger of Allah and follows no one else.

For this reason these two declarations are counted as a single pillar of Islam: they both serve one purpose—validating acts of worship. Worship is only sound when it rests on these two testimonies: “There is no god but Allah,” which secures sincerity, and “Muhammad is the Messenger of Allah,” which secures compliance.

Regarding the words, “and that Muhammad is the Messenger of Allah,” you must utter them with your tongue while affirming with your heart that Muhammad is the Messenger of Allah, sent to all mankind as a mercy for the worlds, as Allah says, “We did not send you but as a mercy to the worlds” (21:107). You must also believe that he is the Seal of the Prophets, as the Exalted says, “Muhammad is not the father of any of your men, but he is the Messenger of Allah and the Seal of the Prophets” (33:40). Consequently, there is no prophet after him; whoever claims prophethood after him is a lying disbeliever, and whoever believes such a claim is likewise a disbeliever.

This testimony further obliges you to follow his law and his sunnah and never to introduce into his religion anything that does not belong to it. Hence we say that the innovators who add to the Prophet’s Sharīʿah what it does not contain have not truly fulfilled the testimony that Muhammad is the Messenger of Allah. Even if they claim to love and revere him, had their love and reverence been complete they would not have preceded him with their own opinions, nor inserted into his Sharīʿah what is foreign to it.

In reality, every innovation contains an implicit slight against the Messenger of Allah ﷺ, as though the innovator were saying: “The Messenger did not perfect the religion or the law, for there remains a matter of religion and law that he failed to bring.” Innovation carries yet another grave danger—it entails denying