They belch out; or, they pour forth, (to wit, words, for what else should come out of the mouth? even sharp and bitter words, as the next clause explains it,) abundantly and vehemently, as a fountain doth waters, as this word signifies. See Proverbs 15:28 Jeremiah 6:7. Swords, i.e. words as keen and mischievous as swords, as Psalms 55:21, Psalms 57:4. Who, say they, doth hear? David doth not hear us, either to discover, and so to prevent our plots; Or to punish us for them; and God either doth not hear or not regard what we say and do against David; and therefore we may speak and act what we think fit.
Related Commentaries of Psalms 59:7
Psalms 59:7
7 Behold, they belch out with their mouth: swords are in their lips: for who, say they, doth hear?