Verses 17, 18. - A warning against vindictiveness, nearly approaching the great Christian maxim, "Love your enemies" (Matthew 5:44). Verse 17. - Rejoice not when thine enemy falleth. "Thou shalt love thy neighbour" was a Mosaic precept (Leviticus 19:18); the addition, "and hate thine enemy," was a Pharisaic gloss, arising from a misconception concerning the extermination of the Canaanites, which, indeed, had a special cause and purpose, and was not a precedent for the treatment of all aliens (see Proverbs 25:21, 22). When he stumbleth; rather, when he is overthrown. The maxim refers to private enemies. The overthrow of public enemies was often celebrated with festal rejoicing. Thus we have the triumph of Moses at the defeat of the Amalekites, and over Pharaoh's host at the Red Sea; of Deborah and Barak over Sisera (Exodus 15; Exodus 17:15; Judges 5); and the psalmist, exulting over the destruction of his country's foes, could say, "The righteous shall rejoice when he seeth the vengeance; he shall wash his feet in the blood of the wicked" (Psalm 58:10). But private revenge and vindictiveness are warmly censured and repudiated. So Cato, 'Distich.' 4:46 -

"Morte repentina noli gaudere malorum;
Felicesobeunt quorum sine crimine vita est." Of very different tone is the Italian proverb, "Revenge is a morsel for God;" and "Wait time and place to act thy revenge, for it is never well done in a hurry" (Trench).

24:17,18. The pleasure we are apt to take in the troubles of an enemy is forbidden. 19,20. Envy not the wicked their prosperity; be sure there is no true happiness in it. 21,22. The godly in the land, will be quiet in the land. There may be cause to change for the better, but have nothing to do with them that are given change. 23-26. The wisdom God giveth, renders a man fit for his station. Every one who finds the benefit of the right answer, will be attached to him that gave it. 27. We must prefer necessaries before conveniences, and not go in debt.Rejoice not when thine enemy falleth,.... These words are spoken not to the wicked man, Proverbs 24:15; but to the just man, or Solomon's son, or the children of Wisdom; for by the "enemy" is meant such who are at enmity with the people of God, as the seed of the serpent, and those after the flesh, are: and when these "fall", saints should not "rejoice"; as when they fall into sin; for so to do would be to act as wicked "charity which rejoiceth not in iniquity", 1 Corinthians 13:6, or rather when they fill into calamity and distress; for this is also the part which wicked men act towards the people of God, and should not be imitated in; see Obadiah 1:12. Joy may be expressed at the fall of the public enemies of God and his people, as was by the Israelites at the destruction of Pharaoh and his host, Exodus 15:1; and as will be by the church at the destruction of antichrist, and which they are called upon to do, Revelation 18:20; partly on account of their own deliverance and safety, and chiefly because of the glory of God, and of his justice displayed therein; see Psalm 58:10; but as private revenge is not to be sought, nor acted, so joy at the calamity and ruin of a private enemy, or a man's own enemy, should not be expressed; but rather he is to be pitied and helped; see Proverbs 25:21; for to love an enemy, and show regard to him, is the doctrine both of the Old and of the New Testament;

and let not thine heart be glad when he stumbleth; even secret joy should not be indulged, gladness in the heart, though it does not appear in the countenance, and is not expressed in words; no, not at the least appearance of mischief, when he only stumbles and is ready to fall; and much less should there be exultation and rejoicings made in an open manner at the utter ruin of him.