He has made it clear that whoever turns away from that is neither following the truth nor truly seeking it. For among the People of the Book, no one whose aim is the truth will turn away from what you have just affirmed; only those who seek dispute and hostility, following the whim of their own souls, turn away—and Allah will relieve you of any concern about them.

If the Quran is indeed from Allah and someone still rejects it, no one is more astray than such a person, for he is mired in deep schism. Even if it is assumed that he does not realize it is the truth, he is nevertheless misguided. Schism may stem from stubborn defiance, or it may arise out of ignorance.

When the signs become manifest and a person still refuses to examine them in the way that leads to knowledge, he is opposing the truth. Hence He said immediately afterwards:

“We shall show them Our signs on the horizons and within themselves until it becomes clear to them that it is the truth.” ⦗Fussilat 41:53⦘

Thus He informs us that He will show His servants—both in the cosmos and within their own souls—signs that demonstrate it is the truth. Then He says:

“Is it not enough that your Lord is Witness over all things?” ⦗Fussilat 41:53⦘

His testimony alone is sufficient, without the need to await further signs, just as He, Exalted is He, says:

“Say: Allah is sufficient as a witness between me and you, and so too is the one who possesses knowledge of the Scripture.” ⦗al-Raʿd 13:43⦘

His bearing witness to the Quran and to Muhammad takes the form of the statements He had already revealed to His earlier prophets, just as He, the Exalted, said concerning the People of the Book: