Jeremiah 6:27-30

27“I have set you as an assayer and a fortress among My people, That you may know and test their way.

28They are all stubborn rebels, walking as slanderers. They are bronze and iron, They are all corrupters;

29The bellows blow fiercely, The lead is consumed by the fire; The smelter refines in vain, For the wicked are not drawn off.

30People will call them rejected silver, Because the Lord has rejected them.”