If your husband were to accuse you of cheating on him, would you be willing to rely on this test to reveal the truth?
The priest shall bring [the suspected adulteress] and have her stand before the Lord. Then he shall take some holy water in a clay jar and put some dust from the tabernacle floor into the water. After the priest has had the woman stand before the Lord, he shall loosen her hair and place in her hands the reminder-offering, the grain offering for jealousy, while he himself holds the bitter water that brings a curse. Then the priest shall put the woman under oath and say to her, “If no other man has had sexual relations with you and you have not gone astray and become impure while married to your husband, may this bitter water that brings a curse not harm you. But if you have gone astray while married to your husband and you have made yourself impure by having sexual relations with a man other than your husband … may the Lord cause you to become a curse among your people when he makes your womb miscarry and your abdomen swell….”
Then the woman is to say, “Amen. So be it.”
…[The priest] is to have the woman drink the water. If she has made herself impure and been unfaithful to her husband, … her abdomen will swell and her womb will miscarry, and she will become a curse. If, however, the woman has not made herself impure, but is clean, she will be cleared of guilt and will be able to have children. (Abridged from Numbers 5:11-31)
Path of the Beagle 