Romans 12:21 - Joseph Benson’s Commentary on the Old and New Testaments

Be not overcome of evil As all are who avenge themselves; but Even if you see no present fruit, yet persevere; and overcome evil with good Conquer your enemies with kindness and patience, which is the most glorious victory, and a victory which may certainly be obtained, if you have the courage to adhere to that which, being good, is always in its own nature, on the whole, invincible, to whatever present disadvantage it may seem obnoxious. Blackwall, after having praised the language in which this precept is delivered, adds, “This is a noble strain of Christian courage, prudence, and goodness, that nothing in Epictetus, Plutarch, or Antonine, can vie with. The moralists and heroes of paganism could not write and act to the height of this.”