Leviticus 24:20
Breach for breach, eye for eye, tooth for tooth: as he hath caused a blemish in a man, so shall it be done to him again. Breach for breach, eye for eye, tooth for tooth: as he hath caused a blemish in a man, so shall it be done to him again.
The rule lays down a civil law given through Moses requiring proportionate punishment, so that the penalty for causing a blemish matches the injury done. It does not permit individuals to avenge themselves, and personal retaliation and personal revenge were forbidden. Jesus sets this rule of equivalent penalty and equal retaliation in contrast with his command not to retaliate against personal wrongs and not to resist evil by retaliation. He teaches his followers, when oppressed, injured, or struck, to endure it with patience and to respond with generosity rather than revenge. That patient and generous response includes going beyond what is demanded.