But don't we already are obeying the Prophet (PBUH) in believing the Qur'an? Wasn't the Prophet (PBUH) the messenger who delivered the Qur'an. It is not as if we recieve the Qur'an directly, we DO believe him (PBUH) when we took Qur'an word for word and accepted it is the truth from Allah. Prophet Muhammed (PBUH) was the one who conveyed to us the Qur'anic verses.
So tell me please why did the Qur'an left out a strict commandment as "kill the apostate" if we are to believe that the attributed hadith is authentic and inspired by Allah (SWT)? Why did Allah (SWT) mentioned apostasy over and over in the Qur'an but mention nothing of worldly punishment? As you know the Qur'an go in great details regarding small specific things like inheritance, when, how, who; the types of divorce; the halal and haram food and so forth. So holy Qur'an is detailed and complete, so rules that are commanded in some attributed hadiths were not mentioned in the Qur'an if we are to take them and apply them?
Response: I'll present to you my same response to brother eselem in another thread concerning apostasy:
Apostasy is mentioned in several places of the qur'an (2:217, 3:86-90, 4:137, 9:66, 9:74, 16:106-109, 4:88-91 and 47:24-27) but in all of those places, the death penalty is not the prescribed punishment. In fact, the death penalty is not prescribed as a punishment for any crime except in ch.5:33 and 45 in which the reason is due to killing someone else or in self defense or causing mischief and disorder in the land or waging war against islam.
But here is the important part. In verse 34 of the same chapter we read "Except those who repent before you have them in your power. So know that Allah is Most Forgiving, Merciful".
Also in ch.2:178 the death penalty is also mentioned but is followed by the option of providing blood-money as a punishment for the victims family if they choose so instead of death.
In summary, where ever the death sentence is mentioned in the qur'an, it is an option to certain crimes, not mandatory. And if the victim repents and wants peace, we as muslims must grant it to them.
Now the issue of apostasy. In ch. 4:88-91, we are told that the muslims were in a disagreement as to how to deal with the hypocrites. You see, there is a difference between a hypocrite and an apostate. A hypocrite is one who declares themself as a muslim and/or goes about preaching to others to follow the religion of islam but all the while they them self do not practice what they preach . An apostate on the other hand is one who openly declares themself as a muslim or take the shahada but later they openly reject the religion. The solution was for the hypocrites to migrate with Muhammad as a test to their faith;(verse 89) for if they are truly muslims they should willingly accept. If they turn away, then seize them and kill them because their turning away would confirm their apostasy.
But now let's read the following verse. (Verse 90)
"Except those who are connected with a people between whom and you there is a pact, or those who come to you, while their hearts shrink from fighting you or fighting their own people. And if Allah had pleased, He could have given them power against you, then they would have surely fought you. So, if they keep aloof from you and fight you not, and make you an offer of peace, then Allah has allowed you no way against them".
This verse confirms that death is not a mandatory punishment for apostacy for if it was then Allah would not say to grant them peace if they wished to do so.
So in conclusion, the death sentence is the punishment for apostacy but we must keep in mind that if the apostates ask for peace and does not cause any war, we as muslims must grant it. I hope this helps.