Jude 1:8 - Matthew Poole's English Annotations on the Holy Bible

Likewise also; notwithstanding so many judgments of God upon others, which should have kept them from the like sins. These filthy dreamers: either this may be taken properly, and joined to the next clause, defile the flesh; and then it may note the impurity of these wretches, who dreamed of what they loved, and acted over that filthiness in their sleep, to which they were so much addicted when awake: or metaphorically, and so they are called dreamers, as having the sense of their minds overcome and laid asleep by their sensual pleasures; or being like men in a dream, deluded by their absurd, though pleasing imaginations. Defile the flesh: this notes all those lascivious practices, to which, like the Sodomites, they had given themselves over; and whereby they defiled themselves and others: the lust of uncleanness, as it is in Peter. Despise dominion; in their minds, judgments, desires, they reject, make void, and abrogate civil government, as a thing not fit to be. Dominion; not only governors, but government itself. And speak evil of dignities; either spiritual governors, or rather, civil, called dignities, because of the honourable titles given them, and gifts bestowed on them: see 2 Peter 2:10.