John Gill's Exposition of the Whole Bible
Psalms 52:1
Why boastest thou thyself in mischief?.... Or "in evil" w; in that which is sinful; to glory in riches, wisdom, and strength, which are not in themselves evil, is wrong; and to rejoice in such boastings, all such rejoicing is evil; to be a doer of mischief, or sin, is bad; to make a sport of it, worse; but to glory in it, and boast of it when done, is worse still: to be boasters of evil things, is the character of antichrist and his followers, 2 Timothy 3:2; who not only boast of their merit, their good works, and works of supererogation, and of their riches, and honour, and grandeur, saying, "I sit as a queen", Revelation 18:7; but of their wickedness in shedding the blood of the saints, thinking thereby they do God good service, and merit heaven, and eternal happiness; as Doeg boasted of his slaughter of the priests, and of his gaining the king's favour by it;
O mighty man! referring either to his office, being the chief of Saul's herdmen, and set over his servants, 1 Samuel 21:7; or ironically, to the mighty deed he had done, in slaying the unarmed priests, and putting to death the very sucklings at the breast, and even the innocent sheep, oxen, and asses; or to his great wickedness and power to commit it; though man has no power and free will to that which is good, yet he has to that which is evil; so the Septuagint, Vulgate Latin, and the eastern versions render it, "O thou! mighty in wickedness"; and to the same purpose the Targum paraphrases it, "mighty to shed innocent blood"; and the note of Aben Ezra is, "mighty to do evil". A learned writer x thinks this relates to Saul, and describes him as a man of power and dignity. The character well agrees with the little horn and Romish beast, Daniel 7:20;
the goodness of God [endureth] continually: that is, the love, grace, and mercy of God; this is observed as what is the matter of the saints' boasting, in opposition to the wicked boasting of Doeg; they glory in the love of God, and in that they know him who exerciseth lovingkindness, which is the source of all the blessings of grace and goodness; and in Christ, through whom all are communicated to them; and in him, as made every blessing to them, wisdom, righteousness, sanctification, and redemption: they ascribe the whole of their salvation, and all they have, to the grace of God, and glory in nothing as of themselves, and as though not received of the Lord. Moreover, the psalmist may take notice of this, as what was his support under all the persecutions he endured from men; that he had an interest in the grace and goodness of God, which is immutable and everlasting, invariably the same in all states and conditions; and that he was encompassed about with the favour of God as with a shield; and that it was not in the power of his most implacable enemies to separate him from the love of God; and therefore it was egregious folly in Doeg to boast himself in mischief; for, be he as mighty as he might, he could not prevent his sharing in the divine goodness, which always continues.
w ברעה "in malo", Vatablus, Junius Tremellius, Gejerus. x Delaney's Life of King David, vol. 1. p. 119.