Although, in the eyes of Islam, the right to life is considered a divine gift and the most important inherent right of mankind and thus safeguarding it is a divine duty for both the people and the state. Using any tools that can totally or partially destroy the source of mankind, is banned and unlawful.1
But we must not misunderstand that the right to life in Islam is absolutely without any exceptions. This right enjoys sanctity as long as the life of another man is not endangered. Or perhaps there is a more important necessity aimed at perfection of mankind which, as an exception, might call for termination of somebody's life.
The followings are brief cases of such exceptions:
A- Retaliation decree: As explained before, in the eyes of the enlightening religion of Islam retaliation is not merely depriving the killer of his life, but the philosophy of its legality is countering unlawful violation of mankind's right to life, so it is a guarantee to the survival of mankind. Additionally, retaliation in fact is a just and fair punishment and a conventional practice. The execution of retaliation would relief the public's Conscience which was wounded and not at ease because of a murder.
B-Abortion if urgency calls: As explained in details previously Islam does not only protects right to postnatal life but also prenatal life (since the earliest stage of formation of embryo in a mother's uterus.)
In the eyes of Islam life during the prenatal life (embryo's) and even before an embryo is formed is subject to protection. Depriving an embryo of life through abortion is a crime and a sin. And he who commits this crime is entitled to punishment. And deprivation of life will not be lawful unless due to a proper justification.
But sometimes it is possible that the continuation of pregnancy would be endangering a mother's life or health or might cause extraordinary difficulties for the mother. Should urgency rise and in the above cases abortion is allowed as an emergency as considered the priority, and so the life of an embryo can be terminated. Also if an embryo is found dead in the uterus of a mother, abortion would be allowed.
C-Fighting against God and the Prophet and the corruption on the Earth: In Islam a man who practically tries to stand against God and oppose an Islamic system is considered a belligerent and corruption on the Earth. A punishment has been defined and determined for him. To what extent should he be punished depends on intensity, type and extent of the measures taken by him: If he has committed a murder he deserves death penalty and execution. The Holy Quran says in this issue:
إِنَّمَا جَزَاءُ الَّذِينَ يُحَارِبُونَ اللَّهَ وَرَسُولَهُ وَيَسْعَوْنَ فِي الْأَرْضِ فَسَادًا أَنْ يُقَتَّلُوا أَوْ يُصَلَّبُوا أَوْ تُقَطَّعَ أَيْدِيهِمْ وَأَرْجُلُهُمْ مِنْ خِلَافٍ أَوْ يُنْفَوْا مِنَ الْأَرْضِ ۚ ذَٰلِكَ لَهُمْ خِزْيٌ فِي الدُّنْيَا ۖ وَلَهُمْ فِي الْآخِرَةِ عَذَابٌ عَظِيمٌ
Indeed, the penalty for those who wage war against Allah and His Messenger and strive upon earth [to cause] corruption is none but that they be killed or crucified or that their hands and feet be cut off from opposite sides or that they be exiled from the land. That is for them a disgrace in this world; and for them in the Hereafter is a great punishment. (Quran, 5:33)
Apparently committing such deeds which (threatens and) infringes upon the security of the general public and creates fear in people, in proportion to the extent to which he has acted, would be followed by the punishment of the convict.
- 1. Declaration of Human Rights in Islamic Law, Article 2, B.