﴿ يَٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُوا۟ كُتِبَ عَلَيْكُمُ ٱلْقِصَاصُ فِى ٱلْقَتْلَى ۖ ٱلْحُرُّ بِٱلْحُرِّ وَٱلْعَبْدُ بِٱلْعَبْدِ وَٱلْأُنثَىٰ بِٱلْأُنثَىٰ ۚ فَمَنْ عُفِىَ لَهُۥ مِنْ أَخِيهِ شَىْءٌۭ فَٱتِّبَاعٌۢ بِٱلْمَعْرُوفِ وَأَدَآءٌ إِلَيْهِ بِإِحْسَٰنٍۢ ۗ ذَٰلِكَ تَخْفِيفٌۭ مِّن رَّبِّكُمْ وَرَحْمَةٌۭ ۗ فَمَنِ ٱعْتَدَىٰ بَعْدَ ذَٰلِكَ فَلَهُۥ عَذَابٌ أَلِيمٌۭ ﴾

“O YOU who have attained to faith! Just retribution is ordained for you in cases of killing: the free for the free, and the slave for the slave, and the woman for the woman. And if something [of his guilt] is remitted to a guilty person by his brother, this [remission] shall be adhered to with fairness, and restitution to his fellow-man shall be made in a goodly manner. This is an alleviation from your Sustainer, and an act of His grace. And for him who, none the less, wilfully transgresses the bounds of what is right, there is grievous suffering in store:”

Islam has laid down the principle of retaliation in like measure (qisas). For example, ‘an eye for an eye and a tooth for a tooth’. Retribution for a killer means the forfeiture of his own life. In this way, on the one hand, a capital crime like the taking of life is effectively discouraged, for the fear of losing one’s own life deters one from taking another’s life and, as a result, the life of all the members of a society become protected. The killing of the killer guarantees the saving of lives in a society. Thus the objective of qisas is the protection of the members of society, and not revenge. Moreover, the vengeful feelings of the family of the murdered person are cooled, thus obviating the possibility of any further injurious activity. However, qisas in Islam permits a settlement to be arrived at between the killer and the killed. The heirs of the deceased person may, of course, opt for the execution of the killer, but they may also, if they so wish, accept blood-money instead, or even forgive him. The main aim of these alternatives is to guarantee the prevalence of brotherly feeling in Islamic society, and to prevent an atmosphere of rivalry taking root. Then the principle of blood-money has the special advantage of giving the bereaved family monetary compensation for the death of one of its members.