Ecclesiastes 10:8-10

New Revised Standard Version Updated Edition

⁸ Whoever digs a pit will fall into it,
    and whoever breaks through a wall will be bitten by a snake.^(A)
9 Whoever quarries stones will be hurt by them,
    and whoever splits logs will be endangered by them.
¹⁰ If the iron is blunt and one does not whet the edge,
    then more strength must be exerted,
    but wisdom helps one to succeed.