Commentary
This eighth injunction is about the prohibition of killing unjustly. Virtually all groups, religions and sects of the world take it to be a grave crime. In Hadith, the Holy Prophet ﷺ said, "The destruction of the en-tire world is lighter in the sight of Allah than the unjust killing of a believer." In addition to this, some reports also carry the words: "Even if the inhabitants of Allah's seven heavens and seven earths were to join in the killing of a believer unjustly, He will put all of them into the Hell." (Ibn Majah with a chain classified as Hasan and al-Baihaqi - from Mazhari)
And in another Hadith, the Holy Prophet ﷺ has been reported to have said, "Whoever abets in the killing of a believer by assisting the killer even with one word will be brought before Allah Ta’ ala on the day of Resurrection. And written on his forehead shall be: آیس من رحمۃ اللہ (Deprived of the mercy of Allah). (Mazhari from Ibn Majah and Isbahani)
And al-Baihaqi reports on the authority of Sayyidna ` Abdullah ibn ` Abbas and Sayyidna Mu'wiyah ؓ that the Holy Prophet ﷺ said, "Hopefully, Allah Ta` ala may forgive every sin except that of the person who died in the state of disbelief (kufr) or who killed a believer intentionally and unjustly."
The meaning of Unjust Killing
Imam al-Bukhari and Muslim have reported on the authority of Sayyidna ` Abdullah ibn Masud رضی اللہ تعالیٰ عنہما that the Holy Prophet ﷺ said, "The blood of any Muslim who bears testimony that Allah is one and I am His Messenger is not halal (lawful) except under three situations. (1) He has, despite being married, committed adultery (for his legal punishment is that he should be stoned to death). (2) He who has killed a person unjustly [ for his punishment is that the waliyy (legal heir) of the person killed can get him killed under the law of qisas (even retaliation)]. (3) A person who has reneged [ as an apostate: murtadd ] from the religion of Islam (for he too is killed in punishment).
Who has the right to take Qisas?
It has been said in this verse that this is the right of the waliyy (legal heir) of the person killed. In the absence of a lineal waliyy, the head of the Islamic government will have this right - for, he too, in a way, is the waliyy of all Muslims. Therefore, in Islamic juristic terminology, the former is called real and the later, legal.
Injustice is not answered by injustice, but by justice: So, be just even when punishing criminals
The statement: فَلَا يُسْرِف فِّي الْقَتْلِ ('fala yusriffi al-qatl': but he shall not cross the limit in the matter of taking life) is a special provision of Islamic law the outcome of which is that it is not permissible to avenge injustice by counter injustice. Even when retaliating, it is necessary to uphold the demand of justice. Until such time that the legal heir (waliyy) of the person killed upholds justice and seeks an even retaliation in favor of the person killed represented by him, through the legal provisions of Qisas, then, the law of the Shari` ah stands in his favor. The reason is that he is surely supported, and Allah Ta` a1 is the supporter. And in case, he is all blinded by the desire of revenge and exceeds the limits of Islamic legal retaliation, then he, instead of being the one oppressed (mazlum), became the oppressor (Zalim) while the oppressor (zalim) be-came the one oppressed by him (mazlum). Now things will stand reversed. Allah Ta` ala and His Law will not support him. Instead, it will support the other party and shield him from injustice.
During the days of the Jahiliyyah, it was common practice of the Arabs that, in retaliation of a person killed, they would avenge him by killing anyone they could lay their hands on from among the family or friends of the killer. There were occasions when it would turn out that the person killed was someone notable among them. In that case, they would not take it as sufficient to kill only the killer in even retaliation for their man. In fact, to avenge one life, they would take the lives of two, three or many more men. Some of them would become so crazy in the heat of their passion for revenge that they would not be simply satisfied after having killed the killer. They went on to commit the horror of cutting off body parts such as the nose, ears etc. to serve as deterrents. All such actions are extra to the limits set by the Islamic Law of Even Retaliation (al-qisas), and are patently haram (unlawful). Therefore, such activities have been stopped by the proviso: I ) (but he shall not cross the limit in the matter of taking life).
An anecdote worth remembering
Someone accused Hajjaj ibn Yusuf before certain Mujtahid Imams. Hajjaj ibn Yusuf is the most notorious tyrant of Islamic history. Since, he has killed thousands of Sahabah and Tabi` in unjustly, therefore, it generally happens that people tend to overlook the evil lurking behind calling him evil. The pious elder before whom this accusation was leveled against Hajjaj ibn Yusuf asked the accusers, "Do you have any authority or evidence to support your accusation?" They said, "No." Then he said, "If Allah Ta’ ala will avenge the unjust killing of thousands of in-nocent people by Hajjaj ibn Yusuf, remember that anyone who is unjust to Hajjaj will also not be allowed to escape from that revenge. Allah Ta` la will wreak vengeance of Hajjaj from him too. There is no partisanship in the justice of Allah Ta` ala, therefore, it is not possible that He would release others to go about maligning His sinning servants by giving them a free hand to accuse and blame them at will.