Ecclesiastes 10:8-10

Complete Jewish Bible

⁸ He who digs a pit may fall into it;
he who breaks through a wall may be bitten by a snake.
⁹ He who quarries stones may get hurt by them,
he who chops wood puts himself in danger.
¹⁰ If the [hatchet’s] iron [blade] is blunt,
and [its user] doesn’t sharpen it,
he will have to exert more effort;
but the expert has the advantage of his skill.