ANSWER:

This is not prohibited as it is your right to forgive or not to forgive! However, if you forgive people in this world Allah will forgive your sins on the day of judgement

QUESTION: Do we have the right to not forgive someone even tho he did repentance to god and he is sincere about it ? We know that god can forgive anything but not us as humans, is it prohibited?

Character and Morals, Sins |