Psalms 59:7

Behold, they belch out with their mouth - The word rendered “belch out” means properly to boil forth; to gush out, to flow; and then, to pour forth copiously, or in a running stream, as a fountain does. Hence, the word means also to pour out “words” - words that flow freely - words of folly, abuse, or reproach. Proverbs 15:2, “the mouth of fools poureth out (Margin, belcheth or babbleth) foolishness.” Proverbs 15:28, “the mouth of the wicked poureth out evil things;” that is, “gushes over” with wicked things - as a fountain overflows. In this place, the word means that the enemies of David who were in pursuit of his life, poured out reproaches and threatenings like a gushing fountain.

Swords are in their lips - Their words are as sharp swords. See the notes at Psalms 57:4.

For who, say they, doth hear? - That is, no one hears who will be able to punish us. They dread no man; and they have no fear of God. Compare the notes at Psalms 10:11. The words “say they” are, however, supplied here by the translators, and are not in the original; and the language “may” be understood as that of David himself, “as if” no one heard; that is, It is no wonder that they thus pour out words of reproach, for who “is” there to hear and to punish them? The former interpretation, however, is to be preferred. The language expresses the feelings of the enemies of David, who indulged freely in language of abuse and reproach “as if” there were none to hear.