Sometime after God gave Moses the laws about leprosy, It demanded that Moses put them into effect. It also reminded Moses how important confession, atonement, and animal sacrifice were.
God explained that men could try their wives for adultery by bringing the wife before the priest at the altar, offering 1/10 of a bushel of grain, and accuse her. Then the priest would have the woman sit in the tabernacle, unbind her hair, and hold the grain in one hand while drinking “bitter water” (water with dirt in it). Then the priest would incant and curse at her. If she was guilty, her womb would swell while all her muscles wasted. But if nothing happened, then she would be innocent and her husband would have to take her back.