Numbers 5:15-19

the man shall then bring his wife to the priest, and shall bring as an offering for her a tenth of an ephah of barley meal; he shall not pour oil on it nor put frankincense on it, because it is a grain offering of jealousy, a grain offering of reminder, a reminder of wrongdoing.

‘Then the priest shall bring her forward and have her stand before the Lord,

and the priest shall take holy water in an earthenware container; and he shall take some of the dust that is on the floor of the tabernacle and put it in the water.

The priest shall then have the woman stand before the Lord and let down the hair of the woman’s head, and place the grain offering of reminder in her hands, that is, the grain offering of jealousy; and in the hand of the priest is to be the water of bitterness that brings a curse.

And the priest shall have her take an oath and shall say to the woman, “If no man has had sexual relations with you and if you have not gone astray into uncleanness, as you are under the authority of your husband, be immune to this water of bitterness that brings a curse;