Qur’an is unquestionable proof. Period. Why? The Quran is completely different from all the other books in the world. The Quran, which Prophet Mohamed (SAWS) brought, has challenged all mankind with all their literary geniuses and scientists, from the first day of its revelation to the Last Day, to produce a like of it or even a single chapter of it. The Qur’an is beyond compare from the viewpoint of its styles and eloquence. Prophet Muhammad was unlettered and no one had heard him say even a couple of poetry. However, the Quran also challenged the known experts in poetry and oratory and forced them to surrender.
The Quran describes man with all his physical and spiritual aspects and contains principles to solve all the problems that may appear at any time and in any place concerning all the social, economic, political and administrative fields of life. Furthermore, it satisfies both the mind and spirit at the same time and guarantees happiness in both worlds. The Quran unveils the mystery of man, creation and the universe.
If you have the Qur’an, open these ayat and cross reference with the things I just said: 2:23, 10:38, 11:13, 17:88, 52:34.
2:23 And if ye are in doubt concerning that which We reveal unto Our slave (Muhammad), then produce a surah of the like thereof, and call your witness beside Allah if ye are truthful.
10:38 Or do they say [about the Prophet], “He invented it?” Say, “Then bring forth a surah like it and call upon [for assistance] whomever you can besides Allah , if you should be truthful.”
11:13 Or do they say, “He invented it”? Say, “Then bring ten surahs like it that have been invented and call upon [for assistance] whomever you can besides Allah , if you should be truthful.”
17: 88 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.
52:34 Let them then produce a recital like unto it,- If (it be) they speak the truth!