In many religions, the creed promotes forgiveness versus revenge, and this may not be easy for some people.
For instance, Islam always urges forgiveness even in the direst of circumstances while taking into account the nature of human kinds.
Muslims believe in the Torah or Old Testament’s eye for an eye principle in the case of capital publishment. However, based on Prophet Muhammad's (PBUH) teachings, Muslim are urged to choose the forgiveness path instead of retaliation.
Even in the Quran, some verses refer to this fact, and below are some examples:
"Keep to forgiveness (O Muhammad), and enjoin kindness, and turn away from the ignorant." (Quran 7:199)
"…but whosoever forgives and makes amends, his reward is upon God." (Quran 42: 40)
Another impressive example comes from Christianity, While in agony on the cross, Jesus called out, "O Lord, forgive them, for they do not know what they are doing.” (Luke 23:34).
In the video attached, you can view part of an Iranian series titled 'Under the Vestibule' that presents moments in which a father gets hold of his daughter's murderer and he needs to decide whether to take revenge over forgive.