Christ forbade revenge and transgression; furthermore, He commanded benevolence and mercy in return for injury and evil. Now reflect: among the Christian nations themselves how many sanguinary wars have taken place, and how much oppression, cruelty, rapacity and bloodthirstiness have occurred!
(‘Abdu’l-Bahá, Some Answered Questions, p. 166)
Nevertheless, after a certain time, and through the transgression of both the Muhammadans and the Christians, hatred and enmity arose between them. Beyond this fact, all the narrations of the Muslims, Christians and others are simply fabrications, which have their origin in fanaticism, or ignorance, or emanate from intense hostility.
(‘Abdu’l-Bahá, Some Answered Questions, p. 21-22)
The law of the community will punish the aggressor but will not take revenge. This punishment has for its end to warn, to protect and to oppose cruelty and transgression so that other men may not be tyrannical.
(‘Abdu’l-Bahá, Some Answered Questions, p. 267)