Ecclesiastes 10:10-12

International Standard Version

¹⁰ If someone’s ax is blunt—the edge isn’t sharpened—
    then more strength will be needed.
        Putting wisdom to work will bring success.
¹¹ If a serpent strikes despite being charmed,
    there’s no point in being a snake charmer.

¹² The words spoken by the wise are gracious,
    but the lips of a fool will devour him.