What does Leviticus 5:13 mean?

The priest will handle the offering for that person, making things right between them and God for any of those sins, and they'll be forgiven. The leftover part of the offering belongs to the priest, just like with the grain offering. Leviticus 5:13 - Modern Text Bible

(This verse explains that after the priest performs the ritual, the person is forgiven, and the priest keeps the rest of the offering as his share.)