2 occurrences across the corpus

King James Version

Revelation 16:10

And the fifth angel poured out his vial upon the seat of the beast; and his kingdom was full of darkness; and they gnawed their tongues for pain,

KJV Apocrypha (Catholic Deuterocanon)

Epistle of Jeremiah 6:20

They are as one of the beams of the temple, yet they say their hearts are gnawed upon by things creeping out of the earth; and when they eat them and their clothes, they feel it not.