Whoso rewardeth evil for good,.... As the enemies of David and Christ rewarded them, Psa 35:12; this is base ingratitude, contrary to the law and light of nature; worse than beastly, is really devilish; evil shall not depart from his house; from him and his family; they shall be continually visited with one disease and calamity or another; so hateful and offensive is the sin of ingratitude to God, and therefore ought to be carefully avoided. This might be illustrated by the judgments of God on the nation of the Jews, for their ingratitude to Christ.