Ecclesiastes 10:8
“He that diggeth a pit shall fall into it; and whoso breaketh an hedge, a serpent shall bite him.”
Folly is set in great dignity, and the rich sit in low place.
I have seen servants upon horses, and princes walking as servants upon the earth.
He that diggeth a pit shall fall into it; and whoso breaketh an hedge, a serpent shall bite him.
Whoso removeth stones shall be hurt therewith; and he that cleaveth wood shall be endangered thereby.
If the iron be blunt, and he do not whet the edge, then must he put to more strength: but wisdom is profitable to direct.
Counter-Arguments
The strongest case that this verse does not belong in this theme.

Cross-References
“Whoso diggeth a pit shall fall therein: and he that rolleth a stone, it will return upon him.”
“Whoso diggeth a pit shall fall therein: and he that rolleth a stone, it will return upon him.”
“The wicked worketh a deceitful work: but to him that soweth righteousness shall be a sure reward.”
“He made a pit, and digged it, and is fallen into the ditch which he made.”
“So they hanged Haman on the gallows that he had prepared for Mordecai. Then was the king’s wrath pacified.”