Freedom of conscience is one of the fundamental rights of humans enshrined in the Qur’an; it is therefore, absurd for anyone to suggest that Islam allows putting a person to death simply because of converting to another religion.

Even a casual reader of the Qur’an will not fail to be impressed by its emphasis on the freedom of conscience as a corner stone of its moral structure: To cite a few verses:

“THERE SHALL BE no compulsion in religion. Distinct has now become the right way from [the way of] error: hence, he who rejects the powers of evil and believes in God has indeed taken hold of a support most unfailing, which shall never give way: for God is all-hearing, all-knowing.” (Qur’an: 2: 256);

“If it had been your Lord’s will, all who are in the earth would have believed. Will you, then, force the people to become believers?” (Qur’an chapter, 10: 99)

 “And if they surrender themselves unto Him (i.e. God), they are on the right path; but if they turn away – behold, thy duty (O Muhammad,) is no more than to deliver the message: for God sees all that is in [the hearts of] His creatures.” (Qur’an: 3: 20)

“Hence, pay heed unto God, and pay heed unto the Apostle, and be ever on your guard [against evil]; and if you turn away, then know that Our Apostle’s only duty is a clear delivery of the message [entrusted to him].” (Qur’an: 5: 92)

“BUT IF they turn away [from thee, O Prophet, know that] We have not sent thee to be their keeper: thou art not bound to do more than deliver the message [entrusted to thee].” (Qur’an: 42: 48).

I should further state that the entire moral teachings of the Qur’an are based on the notion of moral responsibility which entails freedom of choice. Therefore, to state that one must be put to death for choosing to disbelieve would only undermine the entire moral edifice of the Qur’an.

Furthermore, Qur’an does not allow anyone to harm those who are leaving in peace, no matter what religion they hold on to. This principle has been clearly stated in the Qur’an:  
“Thus, if they let you be, and do not make war on you, and offer you peace, God does not allow you to harm them.” (Qur’an:4: 90)

In pursuance of this policy, the Prophet, peace be upon him, issued clear directives to his soldiers never to disturb those who are engaged in any form of worship. The policy of living and letting others to live is firmly enshrined in the following verses:

“Say: O disbelievers! I do not worship what you worship, Nor do you worship what I worship…..to you your religion, and to me, mine.” (Qur’an: 109: 1-3; 6).

In full conformity with the above teachings, neither the Prophet, peace be upon him, nor any of the four Righteous Caliphs who succeeded him, were in the habit of hunting down people and executing them for merely changing their religions. Rather, they refrained from doing so except in rare cases involving treason. Treason, however, is another matter. The punishment for treason in the Qur’an is as strict as it is in the Old Testament. But it must never be confused with mere change of religion.

In conclusion: It is absurd for anyone to suggest that Islam advocates killing of people who covert to another religion.