To try to get around this Muslims claim the Bible is corrupted but we know based on manuscripts, etc. that the Old Testament has not been corrupted since before the 3rd century BC (nearly 1000 years before the Qur'an was revealed) and that through textual criticism the New Testament has been restored to what was written 2,000 years ago (over 600 years before the Qur'an was revealed). As such this proves one thing - Muslims just like anyone who believes lies will lie to protect their beliefs.

Outdated Morality: Critics point to certain moral precepts found in the Qur'an and Hadith (e.g., specific physical punishments for crimes, the historical acceptance of slavery) as being reflective of 7th-century Arabian societal norms, rather than the timeless and unalterable word of God.

Geographical Discrepancies: Claims are made that the city of Mecca did not exist as a major pilgrimage site at the time of Abraham, nor does it appear on ancient maps before the 8th century CE. Some older qiblah (direction of prayer) points have been found facing Petra, not Mecca.

Contradictions with the Bible: Islam affirms the validity of the original Torah and Gospel. However, the Bible's core doctrines—such as Jesus being the divine Son of God and his crucifixion for atonement—directly contradict central Islamic beliefs. Critics argue that if the original Bible was true, Islam is false; if the Bible was false, then the foundation for many Islamic figures (Abraham, Moses, Jesus) is removed.

Author's Illiteracy: The Islamic argument that Muhammad was an illiterate (unlettered) prophet, making a human authorship impossible, is challenged by some who say he could still listen to and learn from others with access to various scriptures.

Inimitability Challenge: While Muslims point to the Qur'an's unique linguistic and literary style as proof of its divine origin (inimitability), critics suggest the language reflects the era in which it was written and contains no "impossible" information or unfulfilled prophecies that would require a divine source.