Charles H. Spurgeon on Psalms 119:21

Thou hast rebuked the proud that are cursed. This is one of God's judgments: he is sure to deal out a terrible portion to men of lofty looks. God rebuked Pharaoh with sore plagues, and at the Red Sea "In the foundations of the world were discovered at thy rebuke, O Lord." In the person of the naughty Egyptian he taught all the proud that he will certainly abase them. Proud men are cursed men: nobody blesses them, and they soon become a burden to themselves. In itself, pride is a plague and torment. Even if no curse came from the law of God, there seems to be a law of nature that proud men should be unhappy men. This led David to abhor pride; he dreaded the rebuke of God and the curse of the law. The proud sinners of his day were his enemies, and he felt happy that God was in the quarrel as well as he.

Which do err from thy commandments. Only humble hearts are obedient, for they alone will yield to rule and government. Proud men's looks are high, too high to mark their own feet and keep the Lord's way. Pride lies at the root of all sin: if men were not arrogant they would not be disobedient.

God rebukes pride even when the multitudes pay homage to it, for he sees in it rebellion against his own majesty, and the seeds of yet further rebellions. It is the sum of sin. Men talk of an honest pride; but if they were candid they would see that it is of all sins the least honest, and the least becoming in a creature, and especially in a fallen creature: yet so little do proud men know their own true condition under the curse of God, that they set up to censure the godly, and express contempt for them, as may be seen in the next verse. They are themselves contemptible, and yet they are contemptuous towards their betters. We may well love the judgments of God when we see them so decisively levelled against the haughty upstarts who would fain lord it over righteous men; and we may well be of good under the rebukes of the ungodly since their power to hurt us is destroyed by the Lord himself. "The Lord rebuke thee" is answer enough for all the accusations of men or devils.

In the fifth of the former octave the Psalmist wrote, "I have declared all the judgments of thy mouth, "and here he continues in the same strain, giving a particular instance of the Lord's judgments against haughty rebels. In the next two portions the fifth verses deal with lying and vanity, and pride is one of the most common forms of those evils.