Leviticus 5:4

5:4 or when a person swears an oath, speaking thoughtlessly with his lips, whether to do evil or to do good, with regard to anything which the individual might speak thoughtlessly in an oath, even if he did not realize it, but he himself has later come to know it and is guilty with regard to one of these oaths –

Leviticus 5:17

Unknown trespass

5:17 “If a person sins and violates any of the Lord’s commandments which must not be violated (although he did not know it at the time, but later realizes he is guilty), then he will bear his punishment for iniquity