From the Word
13 If a man returns evil for good, evil will not depart from his house. 14 The beginning of strife is like letting out water; so quit before the quarrel breaks out.
Proverbs 17:13–14, RSV
The heathen everywhere, despite their ignorance of God and his grace, condemned even to the utmost the evil of ingratitude. They regarded it the mother of evils, than which was none more malevolent and shameful. Among many examples in this respect is one left us by a people in Arabia called Nabathians, who had an excellent form of government. So strict were they in regard to this evil that any one found guilty of ingratitude to his fellows was looked upon as a murderer and punished with death.
No sin is more abominable to human nature, and of none is human nature less tolerant. It is easier to forgive and forget the act of an enemy who commits a bodily injury, or even murders one’s parents, than it is to forget the sin of him who repays simple kindness and fidelity with ingratitude and faithlessness; who for love and friendship returns hatred. In the sentiment of the Latin proverb, to be so rewarded is like rearing a serpent in one’s bosom. God likewise regards this sin with extreme enmity and punishes it.
Thus we have the teaching of nature and of reason regarding the sin of men’s ingratitude toward one another. How much greater the evil, how much more shameful and accursed, when manifested toward God, who, in his infinite and ineffable goodness, conferred upon us while yet enemies of him and deserving of the fires of hell, not ten dollars, not a hundred thousand dollars even, but redemption from divine wrath and eternal death, and abundantly comforted us, granting safety, a good conscience, peace and salvation! These are inexpressible blessings, incomprehensible in this life. And they will continue to occupy our minds in yonder eternal life. How much more awful the sin of ingratitude for these blessings as exemplified in the servant mentioned in the gospel to whom was forgiven the debt of ten thousand talents and who yet would not forgive the debt of his fellow-servant who owed him a hundred pence!
Luther, Martin, and John Sander. Devotional Readings from Luther’s Works for Every Day of the Year. Augustana Book Concern, 1915, pp. 378–79.