one says, “One has accepted the other’s statement as true,” but not “He has believed him” (āmana lahu), since it was not a matter beyond his knowledge about which he had entrusted the other. Hence Allah says:

“So Lot believed him.”

“Should we believe two human beings like ourselves?”

“You have believed him.”

“He believes in Allah and believes the believers.”

That is, he accepts as true what they tell him concerning matters beyond his knowledge, regarding them as trustworthy in that respect. Thus, alongside accepting something as true, the term conveys trust and trustworthiness, as both its usage and derivation indicate. Hence they said:

“But you will not believe us.”

That is, you will neither acknowledge our report nor trust it nor feel reassured by it, even if we are telling the truth, because he did not regard them as trustworthy in that matter. Even if they spoke the truth, he would not trust them.

(Third: In Arabic, īmān (“belief”) is not contrasted with declaring something false in the way that tasdīq (“accepting as true”) is. It is well known in Arabic that anyone reporting something may be told, “You have spoken the truth,” or “You have lied,” and one may say, “We accepted his statement as true,” or “We declared it false.” But one does not say of every person reporting something, “We believed him” (āmannā lahu), or “We declared him a liar”; nor does one say, “You believe him” (mu’min lahu), or “You declare him a liar.” Rather, the familiar opposite of īmān is kufr (“disbelief”).

One says, “He is a believer,” or “He is a disbeliever.” Disbelief is not confined to declaring something false. Indeed, if someone were to say, “I know that you are truthful, but I will not follow you. Rather, I will oppose you with hostility, hate you, and defy you rather than agree with you,” his disbelief would be even greater. Since disbelief, which is the opposite of faith, is not merely declaring something false, it follows that faith is not merely accepting something as true. Rather, if disbelief may consist either of declaring something false or of opposition, hostility, and refusal without denying its truth, then faith must consist of accepting the truth together with agreement, loyalty, and submission. Merely accepting something as true is not enough.

Islam therefore forms part of what īmān denotes, just as refusing to submit while accepting the truth forms part of what kufr denotes. Every believer must therefore be a Muslim who submits to the command—and this is action.