Numbers 5:17-18

17And the priest shall take holy water in an earthenware vessel and take some of the dust that is on the floor of the tabernacle and put it into the water.

18And the priest shall set the woman before the Lord and unbind the hair of the woman's head and place in her hands the grain offering of remembrance, which is the grain offering of jealousy. And in his hand the priest shall have the water of bitterness that brings the curse.