Proverbs 26:23 in the King James Version
Burning lips and a wicked heart are like a potsherd covered with silver dross.
Context
22 The words of a whisperer are as dainty morsels, they go down into the innermost parts.
23 Like silver dross on an earthen vessel are the lips of a fervent one with an evil heart.
24 A malicious man disguises himself with his lips, but he harbors evil in his heart.