Human beings are fallible and need guidance due to the limitations of human knowledge and reasoning. Revelation from God provides objective moral values and guidance to prevent chaos, as human judgments on issues like homosexuality and abortion would differ. While science has limitations and is fallible, God as the all-knowing creator can provide perfect guidance and answers on matters of spirituality and existence. The Quran confirms the revelations given to previous prophets like Moses, David and Jesus but those scriptures are not perfectly preserved, in contrast to the Quran which Muslims must believe in its totality.