Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) narrates: In earlier times, people used to kill the murderer in retaliation for the slain, and blood money was not accepted. Allah Almighty revealed this verse: "O you who believe! Retaliation (Qisas) is prescribed for you in the case of those killed," up to the end of the verse: "This is a concession and mercy from your Lord."
Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) says, so Allah Almighty provided you with a concession in this regard which was obligatory upon those before you, meaning He provided a concession in the form of blood money which was not previously accepted. So whoever accepts blood money, then this will be forgiveness, and there should be a following of goodness, and it should be paid by the one to whom it has been easily forgiven by his brother.