1 Samuel 21:14

And Achish said to his servants, Behold, ye see the man is mad: why did ye bring him to me?

Ecclesiastes 7:7

Surely oppression maketh a wise man mad, and a gift destroyeth the heart.

Treasury of Scripture Knowledge

Summary

Then said Achish unto his servants, Lo, ye see the man is mad: wherefore then have ye brought him to me?

Bible References

Is mad

Ecclesiastes 7:7
Surely oppression maketh a wise man mad, and a gift destroyeth the heart.