Leviticus 6:28
The earthen vessel in which it was boiled is to be broken, unless it was boiled in a bronze vessel, in which case it is to be polished very well and rinsed in water.
Leviticus 11:33
Any earthen vessel into which any of these things fall becomes unclean, along with everything in it. You are to destroy it, along with all its contents."
Leviticus 15:12
The earthen vessel that the person with the discharge touches is to be broken in pieces, and every wooden vessel is to be rinsed with water."
Hebrews 9:9-10
This illustration for today indicates that the gifts and sacrifices being offered could not clear the conscience of a worshiper,