Note: While Islaam.Com discourages copying and encourages providing original content on the web, an exception is being made here where an excerpt is copied from another web site. This is an oustanding excerpt, but from a somewhat lengthy and poorly-formated article that can be found on MSA-NEWS.
..Follow us we'll show you a straight path and show you some matters which will prove that the Qur'an is God's word:
FIRST - Because it is the pinnacle of linguistic perfection. The Arabs [of Jahiliyyah] were not accustomed to its form. Their linguistic abilities were hindered by the fact that its expression was worded in the shortest of forms without loss of clear meaning [bayan].
SECOND - Its wonderful structure was unique when it comes to the beginning of verses, their termination, and the places where one stops [when rehearsing it]. This is added to a refined way of presenting truth and the true knowledge of God [`irfan]. Its beautiful word and kind insinuation, easiness of construct and correctness of ordering made the minds of the purest of desert dwellers [al-Arba'] amazed and the understanding of the masters of the tongue struck. The wisdom behind this intended differentiation in which the Qur'an was revealed was to leave no doubt for those with wit [fiTna] or give them reason to steal [by producing something like it].
THIRD - Because the Qur'an has a record of things to come. They came to pass in accordance with the way God has intended. Allah said, "you shall most certainly enter the Sacred Mosque [Mecca], if Allah pleases, in security, (some) having their heads shaved and (others) having their hair cut, you shall not fear." (Surah "The Victory", 48.27)
FOURTH - What it told about previous generations and the people of yore and it was known [to the people of Quraish] that [Mohammed] was but an illiterate who neither read nor wrote. He did not sit with teachers in schools, nor mixed with the learned. He was raised within a people who knew no book. They were naked [`arin] when it came to scientific inquiry [al-ulum al-`aqliyyah]. Allah said, "Surely this Qur'an declares to the children of Israel most of what they differ in." (Surah "The Ant", 27.76).
FIFTH - What it revealed of the secrets of those who opposed it and what they used to plot. Their deceit was revealed to the messenger of God.
SIXTH - That it included knowledge from the smallest of particles to cosmic facts the Arabs did not know in general and neither did Mohammed (peace be upon him); most important, what it included about the science of Shari`ah and how to deduce laws, the ways to logical argumentation [al-hujaj al-`aqliyyah], the wisdom one derives from the stories of yore, the matters of the hereafter and the best of manners and behavior.
SEVENTH - It is free of contradiction despite the fact that it isa large book which includes many facts and various arts. "If it were from any other than Allah, they would have found in it many a discrepancy." (Surah "The Women", 4.82)
EIGHTH - It is a living miracle for it is read everywhere inuniformity, and God has promised to protect it. It is an established argument that, in contrast to other prophets whose miracles disappeared with them, the Qur'an is Mohammed's eternal miracle.
NINTH - Those who read it are not tired of it. Those who hear it are not bothered by it. And those who rehearse it fall in love with it.
TENTH - It includes both proof and proven. Those who understand the meaning know how to derive proof and how to find religious dictum at the same time when they consider both the way it is read and the way it is understood. It is conciseness of words [balaghah] which proves its miraculous character. It is with meaning that one finds God's order and His warning. Learning it by heart [hifdh] has been made easy. The fear that comes to the heart when hearing it and the humbleness that surrounds those reading it are beyond description.
No doubt that as a child when we were taught the Quran from God we did accept well that. It makes a lot of sense and goes with the inherited human awareness of a supreme being and the order in the universe. I do not know how to convince a child that this creation has no creator and this order in the universe came from chaos. Then as we get older as Muslims and our minds become more searching and more exploring we run the Quran in our minds to be sure about our faith. With all the evidences mentioned above and mentioned in other places. The Quran comes as the book of God for one very clear evidence in the Quran which is the authority of the speaker. Very unique character of the Quran and the Bible is the authoritative speech of God. No doubt in the Bible when God talk to the prophets he does that with a very authoritative and prophetic speech but the Quran is the literal word of God which make it even more reflective of God authority.