Numbers 5:14-15

14Then a spirit of jealousy overcomes him and he is suspicious of his wife, when she is impure. Or a spirit of jealousy overcomes him and he suspects his wife, yet she is not impure.

15“Then he should take his wife to the kohen. He must also bring a tenth of an ephah of barley flour as an offering for her. He is not to pour oil or put incense on it, because it is an offering for jealousy, a reminder offering drawing attention to guiltiness.