28 And the priest shall make an atonement for the soul that sinneth ignorantly, when he sinneth by ignorance before the LORD, to make an atonement for him; and it shall be forgiven him.
Numbers 15:28 Cross References - Webster
Leviticus 4:35
35 And he shall take away all its fat, as the fat of the lamb is taken away from the sacrifice of the peace-offerings; and the priest shall burn them upon the altar, according to the offerings made by fire to the LORD: and the priest shall make an atonement for his sin that he hath committed, and it shall be forgiven him.