Leviticus 5:17-19

17“Now if anyone sins and one of Adonai’s commandments that are not to be done, though he did not know it, still he is guilty and will bear his iniquity.

18He is to bring to the kohen a ram without blemish from of the flock, according to your value, as a trespass offering. Then the kohen is to make atonement for him over the sin that he committed unknowingly—and he will be forgiven.

19It is a trespass offering. He is absolutely guilty before Adonai.”