lewdness - determined, deliberate wickedness; from a Hebrew root, “to purpose.”
I have purged thee - that is, I have left nothing untried which would tend towards purging thee, by sending prophets to invite thee to repentance, by giving thee the law with all its promises, privileges, and threats.
thou shalt not be purged ... any more - that is, by My gracious interpositions; thou shalt be left to thine own course to take its fatal consequences.