John Gill Bible Commentary

His mouth is full of cursing,.... Or, "he has filled his mouth with cursing" (e) God and good men, his superiors, himself and others. The word signifies "an oath"; and may design either a profane oath, taking the name of God in vain; or an oath on a civil account, a false oath, taken with a design to defraud and deceive others, as follows, and intends perjury; and this, as applicable to antichrist, regards his mouth speaking great things and blasphemies against God, and uttering curses and anathemas against the saints, Rev 13:5; and deceit and fraud; such as flattery and lying, which are both used by him with an intention to impose upon and deceive. The apostle, in Rom 3:14; renders both these words by one, "bitterness"; which may be said of sin in general, which is a very bitter thing; though it is rolled as a sweet morsel in the mouth of a wicked man, yet in the issue it is bitterness to him: and it is applicable to sinful words, which are bitter in their effects to those against whom they are spoken, or who are deceived and imposed upon by them: and, as they refer to antichrist, may have respect to the lies in hypocrisy spoken by him, and to the deceitfulness of unrighteousness, by which he works upon those that perish, Ti1 4:2; under his tongue is mischief and vanity; alluding to serpents, who have little bags of poison under their teeth; see Psa 140:3; Kimchi and Ben Melech observe, that the heart is under the tongue, being lower than it, and so denotes the wickedness which that is full of, and devises continually, and is latent in it until discovered; and is mischievous iniquity, injurious to God, and the honour of his law, and to fellow creatures; and especially to the saints, whose persons, characters, and estates, are aimed at; but in the issue it is all vanity, and a fruitless attempt, being blasted by God, and overruled for good to him; see Isa 54:17; (e) .