I have set thee for a tower and a fortress among my people, that thou mayest know and try their way. They are all grievous revolters, walking with slanders: they are brass and iron; they are all corrupters. The bellows are burned, the lead is consumed of the fire; the founder melteth in vain: for the wicked are not plucked away. Reprobate silver shall men call them, because the Lord hath rejected them. Jeremiah 6:27-30