Proverbs 12:13 - Ellicott's Commentary On The Whole Bible

The wicked is cursed by the transgression of his lips. — For his words, the product of his evil heart, while designed to injure others, often bring the offender himself into trouble (Psalms 7:16), and moreover, as being the true index of the inner life of the soul, are being stored up as a witness against him at the day of judgment” (Matthew 12:37). The “just man,” on the contrary, avoids all this “trouble.”