for them, in that case, to acknowledge that he is the Messenger of Allah. If they refuse to acknowledge his messengership, then their appeal to his words is no stronger than an appeal to the words of someone who is not a prophet at all—rather, to the words of liars or of people whose truthfulness is uncertain.

It is universally recognized that anyone who is proved to have lied about Allah in what he claims to transmit from Him—or whose veracity is even suspect—cannot be known to be a messenger of Allah, nor to be truthful in everything he reports from Allah. When that certainty is lacking, it can no longer be affirmed that Allah has revealed anything to such a person. Indeed, once his falsehood is established, it becomes clear that Allah has neither revealed anything to him nor sent him, just as the falsehood of Musaylimah the Liar, al-Aswad al-ʿAnsī, and Ṭulayḥah al-Asadī was exposed, and just as the deceit of Mani and others like them was unmasked.