The Qur'an states that it is a perfect book preserved on tablets in heaven (Surah 85:21-22). If the Qur'an is a perfect book from Allah, then there shouldn't be any contradictions in it. Of course, the Muslims will deny any contradictions exist in the Qur'an, but they do. Some of the contradictions below could be debated, but some of them are clearly contradictions.

A contradiction occurs when one statement on a subject excludes the possibility of another. The first one here is a good example. In Surah 19:67, it states that man was created out of nothing. In 15:26, man is created from clay. Since clay is something, we have a contradiction since "nothing" excludes the possibility of "clay." Both cannot be true.

All quotes from the Qur'an, unless otherwise specified

• What was man created from, blood, clay, dust, or nothing?
  • "Created man, out of a (mere) clot of congealed blood," (96:2).
  • "We created man from sounding clay, from mud moulded into shape, (15:26).
  • "The similitude of Jesus before Allah is as that of Adam; He created him from dust, then said to him: "Be". And he was," (3:59).
  • "But does not man call to mind that We created him before out of nothing?" (19:67, Yusuf Ali). Also, 52:35).
  • "He has created man from a sperm-drop; and behold this same (man) becomes an open disputer! (16:4).
• Is there or is there not compulsion in religion according to the Qur'an?
  • "Let there be no compulsion in religion: Truth stands out clear from Error: whoever rejects evil and believes in Allah hath grasped the most trustworthy hand-hold, that never breaks. And Allah heareth and knoweth all things," (2:256).
  • "And an announcement from Allah and His Messenger, to the people (assembled) on the day of the Great Pilgrimage,- that Allah and His Messenger dissolve (treaty) obligations with the Pagans. If then, ye repent, it were best for you; but if ye turn away, know ye that ye cannot frustrate Allah. And proclaim a grievous penalty to those who reject Faith," (9:3).
  • "But when the forbidden months are past, then fight and slay the Pagans wherever ye find them, and seize them, beleaguer them, and lie in wait for them in every stratagem (of war); but if they repent, and establish regular prayers and practice regular charity, then open the way for them: for Allah is Oft-forgiving, Most Merciful," (9:5).
  • Fight those who believe not in Allah nor the Last Day, nor hold that forbidden which hath been forbidden by Allah and His Messenger, nor acknowledge the religion of Truth, (even if they are) of the People of the Book, until they pay the Jizya with willing submission, and feel themselves subdued," (9:29).
• The first Muslim was Muhammad? Abraham? Jacob? Moses?
  • "And I [Muhammad] am commanded to be the first of those who bow to Allah in Islam," (39:12).
  • "When Moses came to the place appointed by Us, and his Lord addressed him, He said: "O my Lord! show (Thyself) to me, that I may look upon thee." Allah said: "By no means canst thou see Me (direct); But look upon the mount; if it abide in its place, then shalt thou see Me." When his Lord manifested His glory on the Mount, He made it as dust. And Moses fell down in a swoon. When he recovered his senses he said: "Glory be to Thee! to Thee I turn in repentance, and I am the first to believe." (7:143).
  • "And this was the legacy that Abraham left to his sons, and so did Jacob; "Oh my sons! Allah hath chosen the Faith for you; then die not except in the Faith of Islam," (2:132).
• Does Allah forgive or not forgive those who worship false gods?
  • Allah forgiveth not that partners should be set up with Him; but He forgiveth anything else, to whom He pleaseth; to set up partners with Allah is to devise a sin Most heinous indeed," (4:48). Also 4:116
  • The people of the Book ask thee to cause a book to descend to them from heaven: Indeed they asked Moses for an even greater (miracle), for they said: "Show us Allah in public," but they were dazed for their presumption, with thunder and lightning. Yet they worshipped the calf even after clear signs had come to them; even so we forgave them; and gave Moses manifest proofs of authority," (4:153).
• Are Allah's decrees changed or not?
  • "Rejected were the messengers before thee: with patience and constancy they bore their rejection and their wrongs, until Our aid did reach them: there is none that can alter the words (and decrees) of Allah. Already hast thou received some account of those messengers," (6:34).
  • "The word of thy Lord doth find its fulfillment in truth and in justice: None can change His words: for He is the one who heareth and knoweth all, (6:115).
  • None of Our revelations do We abrogate or cause to be forgotten, but We substitute something better or similar: Knowest thou not that Allah Hath power over all things?" (2:106).
  • When We substitute one revelation for another,- and Allah knows best what He reveals (in stages),- they say, "Thou art but a forger": but most of them understand not," (16:101).
• Was Pharaoh killed or not killed by drowning?
  • "We took the Children of Israel across the sea: Pharaoh and his hosts followed them in insolence and spite. At length, when overwhelmed with the flood, he said: "I believe that there is no god except Him Whom the Children of Israel believe in: I am of those who submit (to Allah in Islam). (It was said to him): "Ah now!- But a little while before, wast thou in rebellion!- and thou didst mischief (and violence)! This day shall We save thee in the body, that thou mayest be a sign to those who come after thee! but verily, many among mankind are heedless of Our Signs!" (10:90-92).
  • Moses said, "Thou knowest well that these things have been sent down by none but the Lord of the heavens and the earth as eye-opening evidence: and I consider thee indeed, O Pharaoh, to be one doomed to destruction!" So he resolved to remove them from the face of the earth: but We did drown him and all who were with him," (17:102-103).
• Is wine consumption good or bad?
  • O ye who believe! Intoxicants and gambling, (dedication of) stones, and (divination by) arrows, are an abomination,- of Satan's handwork: eschew such (abomination), that ye may prosper," (5:90).
  • (Here is) a Parable of the Garden which the righteous are promised: in it are rivers of water incorruptible; rivers of milk of which the taste never changes; rivers of wine, a joy to those who drink; and rivers of honey pure and clear. In it there are for them all kinds of fruits; and Grace from their Lord. (Can those in such Bliss) be compared to such as shall dwell for ever in the Fire, and be given, to drink, boiling water, so that it cuts up their bowels (to pieces)?" (47:15).
  • Truly the Righteous will be in Bliss: On Thrones (of Dignity) will they command a sight (of all things): Thou wilt recognize in their faces the beaming brightness of Bliss. Their thirst will be slaked with Pure Wine sealed," (83:22-25).

This list was compiled from resources found on the web at Answering Islam, a List of problems in the Quran. and Errors in the Qur'an

How is it possible that people believe in this. I saw a documentary on Islam v. Christianity. It was the most absurd thing I've ever seen in my whole life, loaded with contradictions and obvious flaws. Thanks for this post, I enjoy reading these ^_^.

Isn't it amazing (mind boggling that is), yet so sad that the islamic believe in this junk? Its the book of lies, the devils journal and the devils 'advice'. Thats what it is.

GOD help these people who fall for this.

My friend is muslim, and he always tries to show me flaws in the Bible but all it is, is him misunderstanding what is being said. These are obvious contradictions and flaws, thanks for bringing out the truth.

I have considered doing a study on Islam at my church, and these are definitely things that I will want to consider letting others know about.
I have also discovered that many Muslims believe in a kind of 'purgatory' for nonMuslims who can attain heaven after a period of time there. I don't know if the Koran speaks of this or not. It's also interesting that they also expect 'Prophet' Jesus to usher in the final judgment in the last days. Why not Muhammad?
It is also interesting that their Prophet Muhammad, who they believe is greater than Jesus, never said that he was God. Jesus did.
Muhammad had many wives, one of which a book has been written about her:

HadithVolume 5, Book 58, Number 234:
Narrated Aisha:
The Prophet engaged me when I was a girl of six (years). We went to Medina and stayed at the home of Bani-al-Harith bin Khazraj. Then I got ill and my hair fell down. Later on my hair grew (again) and my mother, Um Ruman, came to me while I was playing in a swing with some of my girl friends. She called me, and I went to her, not knowing what she wanted to do to me. She caught me by the hand and made me stand at the door of the house. I was breathless then, and when my breathing became Allright, she took some water and rubbed my face and head with it. Then she took me into the house. There in the house I saw some Ansari women who said, "Best wishes and Allah's Blessing and a good luck." Then she entrusted me to them and they prepared me (for the marriage). Unexpectedly Allah's Apostle came to me in the forenoon and my mother handed me over to him, and at that time I was a girl of nine years of age.

Those are some things I have come across from my research. Hope it helps too.