Machine summary:
And since the principle of retribution and punishment was established as a divine command for the purpose of providing a lesson and preventing transgression and criminality of individuals, or for any other reason that God knows, regarding the other principle, which is forgiveness, pardon, or the payment of blood money (Diyah) to the victims' kin, He said: ﴿فمن عفی له من أخیه شیء).
[Legislation of Retribution and its Philosophy] Meaning: if a pardon and forgiveness [more or less] regarding retribution occurs on the part of the victim's kin—who are referred to as 'brother' in relation to the killer—and satisfaction is achieved, then there is no longer any retribution, and instead of the punishment of killing, blood money must be paid.
[Retribution and the View of International Law Scholars] This sentence is a causal explanation regarding the legislation of retribution (Qisas) and an expression of the wisdom behind the ruling; for even if it permits pardon, forgiveness, or the receipt of blood money in specific cases and under certain conditions, it must be noted that the primary basis of the ruling is founded upon retribution; because equal retaliation against killers and those who transgress against the lives and honor of people is one of the factors for the stabilization and establishment of the social order and human life.
And among them, I asked about: (فمن اعتدی بعد ذلک), he said: He is the one who accepts the blood money, or forgives, or makes a settlement, and then acts rebelliously and kills the other party.