This verse creates a significant hurdle for the "Total Corruption" theory
Surah 2:11:
"And they say, 'None will enter Paradise except one who is a Jew or a Christian.' That is their wishful thinking. Say, 'Produce your proof, if you should be truthful.'"
Why would Allah ask for 'proof' from a book that he knew was already corrupted and unreliable? If the Bible had been altered to include false doctrines, it could not function as a burhan (a clear, decisive proof).
By demanding that Jews and Christians produce their proof, the Quran is essentially acknowledging that the documents they held contained the objective truth necessary to settle the matter.
The command "Produce your proof" (Hatu burhanakum) implies a physical or intellectual presentation of the Scripture. If the "True Gospel" had been lost or replaced by the four canonical Gospels centuries earlier, the Christians would have had nothing to "produce" but the "corrupted" version.
If that is what they produced, and the Quran accepts the concept of them producing proof, it is validating the Bible we have today as that proof.
If the Quran is the "Criterion" (Furqan), it should be able to show why the produced proof is wrong by referring to the truth. However, in this verse, the burden is placed on the People of the Book to show their evidence. This implies that the Bible itself is a sufficient standard to determine whether their "wishful thinking" is actually supported by God’s previous revelations.
Surah 2:111 inadvertently anchors the Islamic Dilemma by establishing the Bible as the required "proof" for theological claims. By challenging Jews and Christians to bring forth their scriptures to justify their position, the Quran grants the Bible the status of an authoritative and truthful witness.
The Bible is the "proof" Allah demands, then its contents must be preserved and true; yet those very contents—the proof produced—contradict the Quran's core denials of Christ's work and nature.