Matthew 5:44
but I say unto you, Love your enemies, bless them that curse you, do good to them that hate you, and pray for them who traduce you, and persecute you:
Matthew 6:14
for if ye forgive men their trespasses, your heavenly father will also forgive you.
Romans 12:20-21
therefore if thine enemy hunger, feed him; if he thirst, give him drink: for in so doing, you will heap coals of fire on his head .
1 Thessalonians 5:15
Don't allow any one to return evil for evil, but strive to do all the good you can to one another, and to all the world.
1 Peter 3:9
don't return evil for evil, nor calumny for calumny; on the contrary, bestow your benedictions, considering that your vocation obliges you thereto, as a means to obtain the divine blessing.