Jeremiah chapter 13 had Jeremiah being an object lesson to the people of Southern Judah. God told him to get a linen sash, or girdle, or belt, to wear it around his waste and not to wash it.
Later when the sash was dirty, God told Jeremiah to go to the Euphrates and hide the dirty sash in a hole in a rock.
Later he was instructed to go back there and get it. When he found it, it was ruined and profitable for nothing.
God told him that the people of Judah were like that ruined sash--they were not profitable for Him because of their idolatry and sinful ways.
