In elucidating Paul’s command to overcome evil with good, John Donne (1572-1631) notes two lessons in his sermon “On Candlemas”. First, that despite the disposition of the wicked, due to our shared humanity, all people deserve to be loved. Second, we must be circumspect in labeling people enemies and turning our love away from them, as this creates a rupture in a relationship that is difficult, if not impossible, to heal.

Romans 12:20-21

On the contrary:

“If your enemy is hungry, feed him;
    if he is thirsty, give him something to drink.
In doing this, you will heap burning coals on his head.”

Do not be overcome by evil, but overcome evil with good.

Commentary on Romans 12:20-21

St. Augustine cites and approves that saying of the moral philosopher [Seneca], Omnes odit, qui malos odit,“Whoever hates wicked people hates all people.” For if a person will love none but honest people, where shall he find any practice, any object of his love? So if a person will hold friendship with none, nor do offices of society to none, but to good-natured and gentle and supple and sociable people he shall leave very necessary business undone. The most difficult and perverse person may be good ad hoc for such or such a particular use. By good company and good usage, that is, by being mingled with other herbs and ingredients, the very flesh of a viper is made an antidote; a viper does not lose his place in medicine because he is poison. A magistrate ceases not to be a magistrate because he is a wicked person. Much less does a person cease to be a person—and thus to have a title to those duties which are rooted in nature—because he is of a wicked disposition!

“God makes his sun to shine on the good and on the bad, and sends rain on the just and the unjust.” God has made of one blood all humankind; how unkindly then, how inhumane is it to draw blood! We come too soon to the name of enemy, and we carry it too far. Plaintiff and defendant in a matter of trespass must be enemies. Disputes in a problematic matter of controversy that is not concerned with foundations must be enemies. And then all enmity must imply irreconcilableness; once enemies, friends never again. We come too soon to the name, and we stand too long upon the thing. There are offices and duties even to an enemy.

Romans 9-16, ed. Philip D.W. Krey and Peter D.S. Krey, Reformation Commentary on Scripture NT vol. 8, p. 147.