Justice and Forgiveness
Before Islam, vengeance killings and inter-tribal feuds were common and accepted. Islam broke this cycle by instructing Muslims to seek equal justice, and it encouraged forgiveness as the admirable high road. The Qur'an instructs, “Oh you who believe! Stand out firmly for justice, as witnesses to Allah, as against yourselves, or your parents, or your kin; and whether it be against rich or poor. For Allah can best protect both. Follow not the lusts of your own hearts, lest you swerve, and if you distort justice or decline to do justice, verily Allah is well acquainted with all that you do” (Qur'an 4:135).
Eye for an Eye
The rules of Islamic justice stopped the common practice of massive vengeance killings, whereby a murder would be revenged through the deaths of dozens of the perpetrator's family and tribe members. Islam taught that justice must be proportional to the harm done.
Even with the rules of justice in place, the Qur'an reminds Muslims of the value and benefits of forgiveness as opposed to punishment: “Let them forgive and overlook. Do you not wish that God should forgive you? For God is Oft-Forgiving, Most Merciful” (Qur'an 24:22).
The Three-Day Rule
It is an established Muslim tradition based on Muhammad's example that no Muslim should argue or keep away from another for an extended period of time. If Muslims have a disagreement with each other, they may observe a brief cooling-off period. However, as Muhammad instructed, “It is not permissible for a Muslim to be estranged from his brother for more than three days, both of them turning away from the other when they meet. The better of them is the one who is the first to greet the other.”