Leviticus 5:1

Additional Sin Offering Regulations

5:1 “‘When a person sins in that he hears a public curse against one who fails to testify and he is a witness (he either saw or knew what had happened) and he does not make it known, then he will bear his punishment for iniquity.

Leviticus 23:27

23:27 “The tenth day of this seventh month is the Day of Atonement. It is to be a holy assembly for you, and you must humble yourselves and present a gift to the Lord.