Proverbs 25:21-23

New International Version

²¹ If your enemy is hungry, give him food to eat;
    if he is thirsty, give him water to drink.
²² In doing this, you will heap burning coals^(A) on his head,
    and the Lord will reward you.^(B)

²³ Like a north wind that brings unexpected rain
    is a sly tongue—which provokes a horrified look.