The people of Muhammad’s time wanted a sign from him that his message was true. That is not an unreasonable request. Any time a person comes with a revelation from God, some sort of spiritual, amazing confirmation should come with it. Muhammad said that the Koran was the sign they were looking for.

And they say: Why are not signs sent down upon him from his Lord? Say: The signs are only with Allah, and I am only a plain warner (or prophet). Is it not enough for them that We have revealed to you the Book which is recited to them? Most surely there is mercy in this and a reminder for a people who believe. Surah 29:50-51

Is a book enough of a sign? Lots of people write books. There are books that fill libraries. Are all of them signs from God?

Of course not, but if a book comes along that is from God and dictated to a man, it must be raised to a higher standard of proof, accuracy and consistency. Muhammad said he received the inspiration directly by Allah, through the angel Gabriel.

1. By the Star when it goes down,- 2. Your Companion is neither astray nor being misled. 3. Nor does he say (aught) of (his own) Desire. 4. It is no less than inspiration sent down to him: 5. He was taught by one Mighty in Power, 6. Endued with Wisdom: for he appeared (in stately form); 7. While he was in the highest part of the horizon: 8. Then he approached and came closer, 9. And was at a distance of but two bow-lengths or (even) nearer; 10. So did ((Allah)) convey the inspiration to His Servant- (conveyed) what He (meant) to convey. 11. The (Prophet’s) (mind and) heart in no way falsified that which he saw. 12. Will ye then dispute with him concerning what he saw? 13. For indeed he saw him at a second descent, 14. Near the Lote-tree beyond which none may pass: 15. Near it is the Garden of Abode. 16. Behold, the Lote-tree was shrouded (in mystery unspeakable!) 17. (His) sight never swerved, nor did it go wrong! 18. For truly did he see, of the Signs of his Lord, the Greatest! Surah 53:1-18

Muhammad says here:

• Muhammad was not misled, nor does he falsify information.
• The Koran is not his own words.
• The Koran is inspiration from Allah.
• Allah taught Muhammad with wisdom.
• Muhammad saw Gabriel with his own eyes, far away, then very near. He even gives the exact place. His eye sight was good.
• No one can dispute these words.
• Muhammad saw the signs of the Lord.

There have been many books from other religions that all claimed to receive divine inspiration. There have also been a number of impressive literary works that have set off whole religious movements. Buddha had an experience under a tree. L.Ron Hubbard created Scientology based on stories he had written. The Mormon faith started when Joseph Smith was allegedly visited by God and Jesus in his bedroom and in the forest. The Jehovah Witnesses, Hindus, Hare Krishnas, even Dan Brown’s The Da Vinci Code changed the way many perceived their faith. Anton Levay wrote The Satanic Bible under demonic influence.

Which writer is right? Which writer can claim inspiration from Allah?

A book itself cannot be a sign just because it came to an “ordinary person” as Muhammad describes himself. All of the leaders of the other movements called themselves “ordinary” too.

Muhammad says man and demonic forces (Jinn) could not produce such a book as the Koran.

Say: “If the whole of mankind and Jinns were to gather together to produce the like of this Qur’an, they could not produce the like thereof, even if they backed up each other with help and support.” Surah 17:88

If you brought together all of mankind and all spiritual beings, that would be a pretty smart group of people. Certainly they could produce an impressive literary work. People are creative and can create massive works of literature, like Harry Potter, Lord of the Rings and other books. Inspiration alone is not a sign of Allah’s intervention.