Also: Get it off your chest.
Meaning: Tell the truth to relieve your conscience.
Psalm 32:3-5
When I kept silence, my bones waxed old through my roaring all the day long. [4] For day and night thy hand was heavy upon me: my moisture is turned into the drought of summer. Selah. [5] I acknowledged my sin unto thee, and mine iniquity have I not hid. I said, I will confess my transgressions unto the Lord; and thou forgavest the iniquity of my sin. Selah.
Jeremiah 20:9
Then I said, I will not make mention of him, nor speak any more in his name. But his word was in mine heart as a burning fire shut up in my bones, and I was weary with forbearing, and I could not stay.