Ecclesiastes 10:8-11New King James Version (NKJV)
8 He who digs a pit will fall into it,
And whoever breaks through a wall will be bitten by a serpent.
9 He who quarries stones may be hurt by them,
And he who splits wood may be endangered by it.
10 If the ax is dull,
And one does not sharpen the edge,
Then he must use more strength;
But wisdom brings success.
11 A serpent may bite when it is not charmed;
The babbler is no different.