Leviticus 5:4

4 Or when any of you utter aloud a rash oath for a bad or a good purpose, whatever people utter in an oath, and are unaware of it, when you come to know it, you shall in any of these be guilty.

Leviticus 5:4 In-Context

2 Or when any of you touch any unclean thing—whether the carcass of an unclean beast or the carcass of unclean livestock or the carcass of an unclean swarming thing—and are unaware of it, you have become unclean, and are guilty.
3 Or when you touch human uncleanness—any uncleanness by which one can become unclean—and are unaware of it, when you come to know it, you shall be guilty.
4 Or when any of you utter aloud a rash oath for a bad or a good purpose, whatever people utter in an oath, and are unaware of it, when you come to know it, you shall in any of these be guilty.
5 When you realize your guilt in any of these, you shall confess the sin that you have committed.
6 And you shall bring to the Lord, as your penalty for the sin that you have committed, a female from the flock, a sheep or a goat, as a sin offering; and the priest shall make atonement on your behalf for your sin.
New Revised Standard Version Bible, copyright 1989, Division of Christian Education of the National Council of the Churches of Christ in the United States of America. Used by permission. All rights reserved.