John Gill, on Jude 1:15

To execute judgment upon all,.... Quick and dead, small and great, high and low, rich and poor, good and bad, righteous and wicked, sheep and goats; to pass the definitive sentence on each, that of absolution, life, and happiness, on his own people, and that of condemnation, death, and misery, on the wicked; which will be done in the most strict and righteous manner: and to convince all that are ungodly among them; those who are without God, the fear of him love to him, or faith in him; who have lived without the worship of him, or in a false worship; and particularly false teachers are here meant, the same as in Jde 1:4; who will then be convicted in their own consciences, by that clear evidence, and full light, in which things will be set: of all their ungodly deeds; both against law and Gospel: which they have ungodly committed; which they lived in the commission of, and continually practised in a vile manner, publicly, and in defiance of heaven, and with seared consciences: and of all their hard speeches, which ungodly sinners have spoken against him; either "against" God, as the Vulgate Latin version reads, against his being, his perfections, his providence, his purposes, his word, and worship; or rather against Jesus Christ the Lord, who will come to judge them, against his person and offices, his blood, righteousness, and sacrifice; his ministers and people, his truths and ordinances.