The Lord speaks to Moses and Aaron about a man who has an abnormal discharge from his body. He is unclean as long as it lasts, and so is everything he touches: the bed he lies on, the seat, anyone who touches him. Whoever touches those things must wash his clothes, bathe and be unclean until evening. When the man is healed, he counts seven days, washes his clothes, bathes in fresh water and on the eighth day brings two turtledoves or two young pigeons to the priest, who offers one as a sin offering and the other as a burnt offering.
An emission of semen makes a man unclean until evening, and so is any clothing or leather it touches. If a man lies with a woman and there is an emission, both bathe and are unclean until evening.
A woman in her menstrual period is unclean seven days, and whatever she touches becomes unclean. If she has a discharge of blood outside her period or one that lasts long, she is unclean as long as it continues, and when healed she waits seven days and on the eighth brings two birds to the priest to make atonement. The chapter warns that the people must live separate from their uncleanness so they do not die by defiling the tabernacle.