Numbers 5:27
5:27 When he has made her drink the water, then, if she has defiled herself and behaved unfaithfully toward her husband, the water that brings a curse will enter her to produce bitterness – her abdomen will swell, her thigh will fall away, and the woman will become a curse among her people.
Numbers 31:23
31:23 everything that may stand the fire, you are to pass through the fire, and it will be ceremonially clean, but it must still be purified with the water of purification. Anything that cannot withstand the fire you must pass through the water.