Likewise, if Islam were to demand only retaliation, as some other creeds ruthlessly teach, there would be no room for mercy and patience nor for spiritual reform and moral maturity, in which case many fine qualities of man would subside and many moral potentials may never be actualized.
It is common knowledge that the people who are taught to forgive under all circumstances do not, and probably cannot, practice their teachings, because it is not the interest of humanity in the long run, nor is it in the interest of morality itself.
Likewise, the people who are taught to practice stern retaliation have little or no respect for human virtues and care less for moral values as universal rules. But Islam, the Divine foster of human nature, has given the right answer to human problems. To those wrong doers who are looking for a second chance, who may improve or benefit by granting them pardon, forgiveness is recommended and preferable. But against those who might misunderstand the motives of forgiveness or be tempted to pursue the wrong course, equal retaliation is authorized. Thus, the attitude of the Muslim in either case is sound and beneficial. When he forgives, he pleases God, retains the upper hand and contributes to the reformation of the delinquent. And when he retaliates, he defends the right, establishes order and justice, and helps to arrest evil.
Now, which is sound morality? The attitude of the person who is a ruthless avenger indiscriminately? Or the attitude of a Muslim who makes room for mercy and forgiveness, and who allows for extraordinary circumstances? And who is normally sound? The person who forgives because he knows that he is not allowed to retaliate?
Or a Muslim who forgives while he is fully aware that he can lawfully retaliate?
Which is real forgiveness? The one resulting from external compulsion and prohibition not to act otherwise? Or the one resulting from freedom of choice and freedom of action? It is no wonder that the moral principles of Islam are sound, unique, and adaptive. They are the instructions of God, the Source of all goodness and morality.