Leviticus 15 - 16

1 And the Lord spoke to Moses and Aaron, saying, 2 “Speak to the children of Israel, and say to them: ‘When any man has a discharge from his body, his discharge is unclean. 3 And this shall be his uncleanness in regard to his discharge—whether his body runs with his discharge, or his body is stopped up by his discharge, it is his uncleanness ...
— LEVITICUS 15 - 16