Ecclesiastes 10:9-11

Common English Bible

⁹ Whoever quarries stones may be injured by them;
    whoever splits logs
    may be endangered by them.
¹⁰ If an ax is dull
    and one doesn’t sharpen it first,
    then one must exert more force.
It’s profitable to be skillful and wise.
¹¹ If a snake bites before it’s charmed,
    then there’s no profit
    for the snake charmer.