Job 9:20 in the World English Bible
Though I am righteous, my own mouth will condemn me. Though I am blameless, it will prove me perverse.
Context
19 If I speak of strength, lo, he is strong: and if of judgment, who shall set me a time to plead?
20 If I justify myself, mine own mouth shall condemn me: if I say, I am perfect, it shall also prove me perverse.
21 Though I were perfect, yet would I not know my soul: I would despise my life.