Conquer evil men by your gentlekindness

"You ... have not been appointed to decree vengeance upon men’s deeds and works, but rather to ask for mercy for the world, to keep vigil for salvation of all, and to partake in every man’s suffering, both the just and sinner. Rather than be an avenger, be a deliverer. Instead of being a faultfinder, be a soother. Instead of being a betrayer, be a martyr. Instead of being a chider, be a defender. Beseech God in behalf of sinners that they receive mercy, and pray to Him for the righteous that they be preserved. Conquer evil men by your gentle kindness, and make zealous men wonder at your goodness. Put the lover of justice to shame by your compassion. Remember that the sins of all men go before them to the judgment seat."

-- St Isaac the Syrian (+700)
The Ascetical Homilies, pp 313-314