Charles Ellicott Commentary Lamentations 2:16

"All thine enemies have opened their mouth wide against thee; They hiss and gnash the teeth; they say, We have swallowed her up; Certainly this is the day that we looked for; we have found, we have seen it." — Lamentations 2:16 (ASV)

All your enemies. —The exultation of the enemies is expressed by every feature in the physiognomy of malignant hate, the wide mouth, the hissing, the gnashing of the teeth. They exult, as in half-broken utterances, in the thought that they have brought about the misery at which they mock. It is what they had long looked for; they had at last seen it.