It is joy to the, last to do judgment,.... It is with pleasure he does it; he delights in the law of God, after the inward man, and finds much peace of mind and joy in the Holy Ghost in keeping it, and observing its commands, which are holy, just, and good; yea, it gives him pleasure to see justice done by others; both by private persons in their dealings with one another; and especially by judges putting the laws in execution, as their office requires; whereby much good comes to a nation in general, and to particular persons;
but destruction shall be to the workers of iniquity; that make a trade of sinning; whose whole life is a continued series of sin and iniquity; who take much pains in committing sin, and are constant at it; everlasting destruction is in their ways, and they lead unto it: or, "terror" (a) shall be to them; terror of mind now at times, in opposition to the joy and peace a good man finds; and dreadful horror at death and to all eternity: or, as it is joy to a just man to see public justice done, and good laws put in execution, it is a terror to evildoers, Romans 13:3.
(a) "pavor", V. L. "horror", Tigurine version; "terror", Vatablus, Mercerus; "consternatio", Cocceius, Michaelis, Schultens.

There is true pleasure only in the practice of religion.

But the just love right and need no bribes. The wicked at last meet destruction, though for a time happy in concealing corruption.

15 It is a joy to the just to do justice,
And a terror for them that work iniquity.
To act according to the law of rectitude is to these as unto death; injustice has become to them a second nature, so that their heart strives against rectitude of conduct; it also enters to little into their plan of life, and their economy, that they are afraid of ruining themselves thereby. So we believe, with Hitzig, Elster, Zckler, and Luther, this must be explained in accordance with our interpretation of Proverbs 10:29. Fleischer and others supplement the second parallel member from the first: וּפעל און מחתּה לפעלי אין; others render 15b as an independent sentence: ruin falls on those who act wickedly. But that ellipsis is hard and scarcely possible; but in general מחתה, as contrasted correlate to שׂמחה, can scarcely have the pure objective sense of ruin or destruction. It must mean a revolution in the heart. Right-doing is to the righteous a pleasure (cf. Proverbs 10:23); and for those who have און, and are devoid of moral worth, and thus simply immoral as to the aim and sphere of their conduct, right-doing is something which alarms them: when they act in conformity with what is right, they do so after an external impulse only against their will, as if it were death to them.