Romans 12:21
Do not allow yourself to be overcome by evil; on the contrary, he conquers evil with good.
| NIV
Love should be the mentoring principle in Christian relationships, not only between brothers and sisters in faith but also towards enemies.
The apostle Paul mentions many specific Christian duties, but love is the dominant note of his exhortations and really the love of God poured into our hearts is what allows us to fulfill these Christian duties in our lives.
God does not like people who pay badly for bad, he exhorts us to do good when they do us badly since we should not act for the same actions as others. We must make a difference in the world since normally people who do not love God act like that, they do good when they do good to him but pay the same when they do bad to him, but we are different because God has done great things in our hearts and evil already it is not an option in our lives.
Paying bad for bad is taking revenge for the actions of others and instead of taking revenge for ourselves, we must put it in the hands of God and thus leave room for God to take with justice what is convenient for each one