The objection has force if "corruption" means that every trace of the earlier revelation had vanished. But that is not the Quran's teaching. It describes a mixture of preserved truth, concealment, distortion, and disputed interpretation; therefore recognition of Prophet Muhammad (PBUH) could remain possible even if the earlier scriptures were not perfectly preserved.

Why the objection seems decisive

The argument can be stated strongly. The Quran says that the People of the Book had previously recognized the promised messenger, then rejected him when he came:

And when there came to them a Book from Allah confirming what was with them - although before that they used to pray for victory against those who disbelieved - then when there came to them what they recognized, they disbelieved in it. So the curse of Allah is upon the disbelievers.

Quran 2:89

If the earlier scriptures had been corrupted before the seventh century, the argument continues, then the Jews and Christians no longer possessed a reliable description of Muhammad (PBUH). The Quran would then be appealing to a broken witness while condemning them for failing to read it. If no trustworthy prediction remained, the indictment would indeed collapse.

What the Quran means by corruption

The Quran does not say that every word of every earlier scripture was erased or that nothing true remained. It speaks of people concealing parts of revelation, misrepresenting words, and twisting meanings. For example:

They distort words from their proper places and have forgotten a portion of what they were reminded of.

Quran 5:13

It also says:

O People of the Book, Our Messenger has come to you making clear to you much of what you used to conceal of the Scripture.

Quran 5:15

Thus, "tahrif" in the classical Muslim discussion includes both textual alteration and interpretive or deliberate concealment. Those ideas are not identical to total destruction. A document can contain genuine material while also suffering additions, omissions, mistranslations, and disputed readings.

How recognition could still occur

Recognition does not require that every earlier manuscript be flawless or that every member of the People of the Book accept Muhammad (PBUH). It requires that sufficiently clear signs remained available to some knowledgeable people: his lineage, character, message, opposition to idolatry, and confirmation of the prophets before him. A reader could recognize a known description even if other passages had been obscured.

The wording "what they recognized" also concerns the reaction of those addressed, not a claim that the entire Jewish or Christian community possessed an unaltered Bible. Some recognized the truth and accepted it; others rejected it despite recognizing the messenger or the truth of his message. The Quran's charge is therefore moral: they did not merely lack evidence; some resisted evidence that had reached them.

What this establishes - and what it does not

This does not prove that every verse in the present Bible is corrupt, nor does it by itself identify a particular surviving passage as a prophecy of Muhammad (PBUH). Those require separate historical and exegetical arguments. It does establish that the Quran's doctrine is coherent: partial preservation and partial distortion can coexist, and recognition can rest on preserved signs rather than a perfectly transmitted text.

So the corruption argument defeats only an exaggerated version of Islamic teaching. It does not refute the Quran's actual claim.