Apostacy

Statement of an atheist: Islam is extremely possessive of its subjects. It is a religion that admits anyone into itsfold by the person simply uttering a one-sentence statement of faith, shahada: "I bear witness that there is no God but Allah, and Muhammad is Allah's messenger." By so saying, one becomes Muslim for life and surrenders theright to ever leave it. Anyone who leaves the Islamic fold is murtad(revert), or an apostate.
Answer: This is an incorrect belief, though certain sects strongly do believe in it. As I understand it from the Quran, there is no compulsion in religion, and those who enter the fold of Islam and then leave it, can enter again. This is only possible if they're alive, not if they are killed for apostasy.
Related verses from the Holy Quran:
2:256 There is no compulsion in religion. The right direction is henceforth distinct from error. And he who rejecteth false deities and believeth in Allah hath grasped a firm handhold which will never break. Allah is Hearer, Knower.
4:137 Those who believe, then reject faith, then believe (again) and (again) reject faith, and go on increasing in unbelief,- Allah will not forgive them nor guide them on the way.
10:99 If it had been thy Lord's will, they would all have believed,- all who are on earth! wilt thou then compel mankind, against their will, to believe!
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