Howcome the quran in one verse says that there should be no compulsion in religion whilst other verses clearly state that anyone who leaves islam is an apostate who deserves eternal damnation? The hadiths or life stories of muhammad clearly bear witness to the fact that critics of islam or anyone who left islam was put to death. The explanation is very simple. The quran has two distinct periods; The first in Mecca was when muhammad started preaching and he tried to be conciliatory to christians, jews and even pagans. When after ten years the meccans failed to be impressed by his visions and revelations muhammad travelled to medina. There he claimed that the meccans were trying to kill him and that allah had given him a new revelation ordering him to plunder carovans and attack vilages killing all the males including prebuscent teenagers whilst keeping children and women to be used as slaves. The nature of the verses in this second period became far more bloody and bellicose. The problem in the quran is that there is no chronological order to the mecca and medina verses and they have been garbled together making the reading very confusing. Again we have a clear example of muhammad making up verses when he decided to become a slave trader and war lord. If you follow the link to the wars of muhammad on the left you can read the chilling stories of how the medina verses were applied during warfare and the resulting acts of vengeance and slave trade.

Muhammad also stated the doctrine of abrogation which means that previous mecca are no longer valid and have been replaced by later medina verses but the most amazing thing is that he did not eliminate from the quran the abrogated verses making it very confusing for a beginner to understand what the islamic doctrine is really saying. The doctrine of abrogation is clearly a poor excuse by muhammad to hustify himself when he wrote contradictory verses, when he forgot verses and a justification to cancel previous conciliatory verses with more violent ones. In Asbab al-Nuzul, p. 19, Suyuti says that, "Ibn ’Abbas himself said, ‘Sometimes the revelation used to descend on the prophet during the night and then he forgot it during daytime, thus God sent down this verse: 2:106." [quran 2: 106] 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?" quran 16:101"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."

Duplicity of muhammad, changing verses when it suited him

We stayed for a short while (after we had covered a little distance), and then I said to my companions, "Allah's Apostle has forgotten his oath. By Allah, if we do not remind Allah's Apostle of his oath, we will never be successful." So we returned to the Prophet and said, "O Allah's Apostle! We asked you for mounts, but you took an oath that you would not give us any mounts; we think that you have forgotten your oath.' He said, 'It is Allah Who has given you mounts. By Allah, and Allah willing, if I take an oath and later find something else better than that. then I do what is better and expiate my oath.' Bukhari:7.427

Why did 'allah' show such a fickle and contradictory mind that he kept changing his ordinances and even cause muhammad to forget verses? Why have abrogated verses been kept in the quran making it terribly confusing for a muslim to know whether a particular verse is still valid or not? Read an article from a muslim website about the confusion amongst muslims about abrogation.

Very good video on this subject

The order for Muslims to be patient and forgiving was issued when they were few and weak, but when they became strong, they were ordered to fight and the previous verses were abrogated" (suyuti 'itqan' part 3, p. 61).

In the final analysis, 71 Suras - out of 114 - comprising 62.28% of all the suras of the Quran have had verses changed or deleted. (Abu Ja'afar al Nakhass ' al Nasikh wal Mansukh').

Mecca:

be patient with the unbelievers:.
73:10 And bear with patience what they utter, and part from them with a fair leave-taking. [3, Mecca ]

Medina:

curse the unbelievers:
22.72 When Our Clear Signs are rehearsed to them, thou wilt notice a denial on the faces of the Unbelievers! they nearly attack with violence those who rehearse Our Signs to them. Say, "Shall I tell you of something (far) worse than these Signs? It is the Fire (of Hell)! Allah has promised it to the Unbelievers! and evil is that destination!"

33:57] Surely, those who oppose GOD and His messenger, GOD afflicts them with a curse in this life, and in the Hereafter; He has prepared for them a shameful retribution.

Mecca:

Do not use coercion with the infidels.
50:45 We are Best Aware of what they say, and thou (O Muhammad) art in no wise a compeller over them. But warn by the Qur'an him who feareth My threat.

Medina:

"In order that Allah may separate the pure from the impure, put all the impure ones [i.e. non-Muslims] one on top of another in a heap and cast them into hell. They will have been the ones to have lost." (Sura 8.37)

Certainly! Allâh will admit those who believe (in the Oneness of Allâh Islâmic Monotheism) and do righteous good deeds, to Gardens under which rivers flow (Paradise), while those who disbelieve enjoy themselves and eat as cattle eat, and the Fire will be their abode. 47:12

Mecca:

Be patient with the unbelievers; Allah will judge them.
10:109 And (O Muhammad) follow that which is inspired in thee, and forbear until Allah give judgment. And He is the Best of Judges. [51, Mecca

Medina:
Amputate and crucify the unbelievers:

5:33 The only reward of those who make war upon Allah and His messenger and strive after corruption in the land will be that they will be killed or crucified, or have their hands and feet on alternate sides cut off, or will be expelled out of the land. Such will be their degradation in the world, and in the Hereafter theirs will be an awful doom;

"Allah revealed His will to the angels, saying: 'I shall be with you. Give courage to the believers. I shall cast terror into the hearts of the infidels. Strike off their heads, strike off the very tips of their fingers!' That was because they defied Allah and His apostle. He that defies Allah and his apostle shall be sternly punished by Allah." (Sura 8.12-13)

Mecca:

Show kindness and tolerance towards the infidels.
7:199 Keep to forgiveness (O Muhammad), and enjoin kindness, and turn away from the ignorant.

Medina:

Kill the critics and do not make friends with unbelievers
9.061 Among them are men who molest the Prophet and say, "He is (all) ear." Say, "He listens to what is best for you: he believes in Allah, has faith in the Believers, and is a Mercy to those of you who believe." But those who molest the Messenger will have a grievous penalty. ( In the link 'leaving Islam' you will find many events where Muhammad had numerous critics murdered )

Qur'an 5:51 "O believers, do not hold Jews and Christians as your friends. They are friends of one another; and anyone who makes them his friends is one of them."

9.023 O ye who believe! take not for protectors your fathers and your brothers if they love infidelity above Faith: if any of you do so, they do wrong

Mecca:

Do not force the infidels into Islam and don't be harsh with them
10:99: And if thy Lord willed, all who are in the earth would have believed together. Wouldst thou (Muhammad) compel men until they are believers?

Medina:

Anyone who does not accept islam will be cursed for eternity

9:73 O Prophet! Strive against the disbelievers and the hypocrites! Be harsh with them. Their ultimate abode is hell, a hapless journey's end.

22:19 These twain (the believers and the disbelievers) are two opponents who contend concerning their Lord. But as for those who disbelieve, garments of fire will be cut out for them; boiling fluid will be poured down on their heads [103, Medina ]

22:20 Whereby that which is in their bellies, and their skins too, will be melted; [103, Medina ]

22:21 And for them are hooked rods of iron. [103, Medina ]

22:22 Whenever, in their anguish, they would go forth from thence they are driven back therein and (it is said unto them): Taste the doom of burning.

Another example of muhammad changing verses to suit himself or the situation

Ishaq:326 "Abdullah told me that when this verse came down it was a shock to the Muslims who took it hard. They were afraid, as the odds were too great. So Allah relieved them and cancelled the verse with another:

8. 65: O apostle! rouse the believers to the fight. If there are twenty amongst you patient and persevering they will vanquish two hundred: if a hundred they will vanquish a thousand of the unbelievers: for these are a people without understanding.

The ratio in this verse is One:Ten. Muhammad's followers complained bitterly at these impossible odds and Allah - as usual - promptly changed

'his mind' and reduced the odds to the more manageable, One:Two, by 'revealing' the next verse ***

8. 66: 'Now has Allah relieved you and He knows that there is a weakness among you, so if there are 100 [rather than 20] they shall vanquish 200.'"

good link to abroagtion - another good link to abrogation