Here the wise man's speech is represented by his "mouth." Alternate translation: "The things that a wise man says are gracious" (See: [[rc://en/ta/man/translate/figs-metonymy]])
Here the fool's speech is represented by his "lips." This speaks of the fool destroying himself by his speech as if it were eating him. Alternate translation: "The things that a foolish man says destroy him" (See: [[rc://en/ta/man/translate/figs-metonymy]] and [[rc://en/ta/man/translate/figs-metaphor]])