an eye for an eye and a tooth for a tooth

Từ điển Oxford Advanced Learner 8th

an ˌeye for an ˈeye (and a ˌtooth for a ˈtooth) idiom
(saying)used to say that you should punish sb by doing to them what they have done to you or to sb else
•They advocate a justice system that works on the principle of an eye for an eye.
Main entry: ↑eye_idiom