Read Jeremiah 2:22 Using Other Translations
For though thou wash thee with nitre, and take thee much soap, yet thine iniquity is marked before me, saith the Lord GOD.
Though you wash yourself with lye and use much soap, the stain of your guilt is still before me, declares the Lord GOD.
No amount of soap or lye can make you clean. I still see the stain of your guilt. I, the Sovereign LORD, have spoken!