Excerpts take from The Malay Ideals (GBC 2002)
The issue of apostasy and its punishment is one of these areas prone to controversy. In Islam, every individual is given the right to choose his own religion. There is a hadith narrated by Bukhari conveying the story of a certain Christian who came into Islam and later reverted back to Christianity. He was never sentenced to any form of punishment for renouncing Islam.
During the time of the Prophet, the death sentence was pronounced on those who had come under the fold of Islam for espionage to find weaknesses in the nascent Muslim community and to feed information back to the enemies of Islam and for those after their conversion out of Islam pronounced war on the Muslim community. Islam for these individuals was a front to be accepted into the community and once they were in, they embarked upon their illicit intelligence work. Thus, when the Prophet pronounced the death penalty upon these apostates, it was pronounced on the basis of treason.
Furthermore, in a climate of constant warfare and bouts of hostility that erupted between the people of Medina and the people of Mecca, conversion out of Islam and vice versa by an individual is synonymous with a change in allegiance. Defection in religion was tantamount to a declaration of war against the respective parties. During this formative stage of Islam's political ascendancy, there was a need to prevent these sorts of events that could rattle Islam's social and power base * apostasy being the greatest threat. The threat of the death sentence for those who renounced Islam would nip the problem in the bud. Treason anywhere in the world is still to this day meted out with capital punishment. The purpose of which is none other than deterrence and for compromising national security. But to many Muslims who are proponents of the death sentence, the change of religion out of Islam for the mere reason of disbelief is considered to merit the death penalty also. They usually quote the hadith "Whoever changed his religion, then kill him." If taken literally, this also means that had someone accepted Islam and renounced his former religion, he would also be killed, which of course makes no sense. It only makes sense if high treason is involved. It is also significant that out of the ayahs (verses) that mention apostasy in the Holy Qur'an, none mentioned punishment for apostates in this world. They gave assurance that the apostates will be punished in the hereafter.
The freedom of religion is guaranteed in Islam otherwise it would be unfair to expect everybody who was born a Muslim not to have the freedom given to those who were born outside Islam and to chose a religion of their own. Every human being either born a Muslim or otherwise has the right to his choice of religion. This is only just. However, having said this, in the case of Malaysia, where there is a delicate balance of the differing ethnic groups, conversion out of Islam may merit special attention. It is of course arguable that reneging Islam, can be interpreted as amounting to a threat of national security since the definition of a Malay person is inextricably linked to a profession of Islam as his faith. Furthermore, conversion out of Islam is highly inflammatory to the sensitivity of Muslims in the country especially when Muslims regard themselves of having been marginalised in many areas of human endeavour. Desertion of Islam is seen as the final blow to their self-esteem and a threat. In such a setting of delicate balance where mass conversions will inevitably engender religious dissension, the death punishment, or other less intrusive laws may be appropriate to act as a deterrence if national security is at stake.