Job 9:30
"If I wash myself with snow water, and make my hands never so clean;"
Cross References (ranked by relevance)
For though thou wash thee with nitre, and take thee much soap, yet thine iniquity is marked before me, saith the Lord GOD.
I will wash mine hands in innocency: so will I compass thine altar, O LORD:
If my step hath turned out of the way, and mine heart walked after mine eyes, and if any blot hath cleaved to mine hands;
For they being ignorant of God’s righteousness, and going about to establish their own righteousness, have not submitted themselves unto the righteousness of God.
O Jerusalem, wash thine heart from wickedness, that thou mayest be saved. How long shall thy vain thoughts lodge within thee?
He that covereth his sins shall not prosper: but whoso confesseth and forsaketh them shall have mercy.