Leviticus 15:2-4

2“Speak to the sons of Israel, and say to them, ‘1When any man has a discharge from his 2body, 3his discharge is unclean.

3This, moreover, shall be his uncleanness in his discharge: it is his uncleanness whether his body allows its discharge to flow or whether his body obstructs its discharge.

4Every bed on which the person with the discharge lies becomes unclean, and everything on which he sits becomes unclean.