The believers do not fall prey to the tyrants. Their tender heartedness and forgiving nature is not the result of any weakness. Their nobility demands that when they are victors they should forgive the errors of the vanquished; when they possess the power, they should avoid vengefulness and when a weak or subdued person happens to commit a mistake they should overlook it; but when a powerful person, drunk with authority, commits violence against them, they should resist and fight him with all their might.
These verses introduce three basic principles of retaliation:
1. The right limit of retaliation is that one should return the same sort of ill treatment that one has received; one has no right to return a greater ill treatment.
2. Although it is permissible to retaliate against the one who has committed violence, wherever pardoning can be conducive to reconcilement, pardoning is better for the sake of reconcilement than retaliation. And since man pardons the other by suppressing his own feelings, Allah says that the reward of such a one is with Him, for he has suppressed his own self for the sake of reforming the evil-doers.
3. One should not become a wrongdoer oneself in the process of avenging a wrong done by the other. It is not permissible to do a greater wrong in retaliation for the wrong done. For example, if a person slaps another, the other can return only one slap; he cannot shower his blows and kicks. Likewise, it is not right to commit a sin in retaliation for a sin. For example, if a wicked man has killed the son of someone, it is not right to go and kill the son of the former. Or, if a person has violated the chastity of another person's sister or daughter, it is not lawful for him to rape the former's sister or daughter.
"The Meaning of the Quran" - By Sayyid Abul Ala Mawdudi, Vol. 4, pp. 551, 552