Leviticus 14:13-14

13He will then slaughter the male lamb in the sacred area where sin offerings and burnt offerings are slaughtered. As with the sin offering, the guilt offering belongs to the priest. It is a most holy offering.

14The priest will then take some of the blood of the guilt offering and apply it to the lobe of the right ear, the thumb of the right hand, and the big toe of the right foot of the person being purified.