Leviticus 5:4-6

New International Version

⁴ or if anyone thoughtlessly takes an oath^(A) to do anything, whether good or evil^(B) (in any matter one might carelessly swear about) even though they are unaware of it, but then they learn of it and realize their guilt— ⁵ when anyone becomes aware that they are guilty in any of these matters, they must confess^(C) in what way they have sinned. ⁶ As a penalty for the sin they have committed, they must bring to the Lord a female lamb or goat^(D) from the flock as a sin offering^[a];^(E) and the priest shall make atonement^(F) for them for their sin.