What does the Quran say about the previous books? Were these books textually corrupted or were they available in an intact form at the time of the revelation of the Quran?
The following Quranic verse may indicate that they were indeed available intact:
[5:47] And the people of the Injeel shall rule in accordance with what God has brought down therein. Those who do not rule by what God has brought down are the wicked.
Until 100 years ago it was thought that only man and animals were in pairs (males and females). However the Quran said that everything from which the land produces, man and what they could not see were also made of pairs. Today we know that all matter is in pairs: matter and antimatter, electrons and positrons, quarks and antiquarks, day and night, male and female, …
Water on Earth actually came from outer space, particularly from ice in comets and meteors. When those comets enter our atmosphere the heat generated on entry vaporizes this ice into the atmosphere. Moslems say that this is what Allah says.
[Quran 2.164] … In the water which Allah sent down from the Heavens and brought with it life to Earth after being dead and gave life in it to every kind of land animal; And in directing the winds; And in the clouds that are enslaved between the Heavens and the Earth; [All these] are Signs for a people who comprehend.
For centuries philosophers thought that only humans were rational while animals only followed instinct. Actually this false belief was so entrenched in Arabs that they included it in their grammar, referring to humans as rational (عاقل) and all other animals, plants and inanimate objects as irrational (غير عاقل). However today scientists have confirmed that animals do not act by instinct alone, as Arabs thought, but rather animals have their own logic and communication systems, that is, they make rational decisions like humans but at a much lower scale…However the Quran did not make the mistakes of the Arabs, instead it says that ants have their own logic and do communicate with their own species:
[Quran 27.18] Until, when they came upon the valley of the ants, an ant said, “O ants, enter your homes so that you do not be crushed by Solomon and his soldiers while they do not feel it.”
The Christian Bible says that in the beginning God said “Let there be light” Genesis 1:3. However this turned out to be false. The universe was opaque to visible light (non-transparent) and photons couldn’t travel at all. After the Big Bang the universe was primarily Hydrogen, Helium and a tiny bit of Lithium. However when a gas is too hot it becomes ionized (loses the electrons) and becomes opaque (like today’s smoke). In the beginning the universe was opaque to visible light (non-transparent). After 380,000 years the universe cooled enough and it became transparent to visible light. For other wavelengths it was opaque for a billion years. So “Let there be light” turned out to be false. However the Quran correctly said that at the beginning it was SMOKE, that is, a hot non-transparent gas:
[Quran 41.11] Then He directed himself to the Heaven when it was SMOKE, and then said to it and to Earth: “Come willingly or by force” they said “We do come willingly”