Ecclesiastes 10:10-13

¹⁰If iron is folded again, and it is not as before, but is made blunt, it shall be made sharp with much travail; and wisdom shall follow after busyness.

¹¹If a serpent biteth, it biteth in silence; he that backbiteth privily, hath nothing less than it, (or he who privately, or secretly, backbiteth someone is no better).

¹²The words of the mouth of a wise man be grace; and the lips of an unwise man shall cast him down. (The words out of the mouth of a wise person bring him favour; but the lips of an unwise person shall bring him down.)

¹³The beginning of his words is folly; and the last thing of his mouth is the worst error. (His words begin with foolishness; and the last thing out of his mouth is the worst error of all.)