Similar words are found in Romans 12:17. More importantly, behind the instruction of both the present passage and the Romans passage is Jesus’ instruction in Luke 6:27–28: “But I say to you who hear, love your enemies, do good to those who hate you, bless those who curse you, pray for those who abuse you. To the one who strikes you on the cheek, offer the other also.” Jesus himself had applied this principle when he was arrested and abused (see 1 Peter 2:22–23), as did also Stephen (Acts 7:60) and Paul (Acts 26:29; 1 Corinthians 4:12–13). The principle itself is rooted in God’s identity as a God of justice so that he promises to execute vengeance (Deuteronomy 32:35, Deuteronomy 32:41, Deuteronomy 32:43), and so the Christian leaves injustice to God to set straight. This breaks the cycle of retaliation. Given Jesus’ instruction in Luke 6:27–28 and his own example as Peter had just described (1 Peter 2:23), it follows that such conduct is meant to be characteristic Christian behaviour.
9 Do not repay evil for evil or reviling for reviling, but on the contrary, bless, for to this you were called, that you may obtain a blessing.