Leviticus 5:1-3

1And if a soul shall sin, and hear the voice of an oath, and be a witness, whether he hath seen or known of it ; if he doth not utter it, then he shall bear his iniquity.

2Or if a soul shall touch any unclean thing, whether a carcase of an unclean beast, or a carcase of unclean cattle, or the carcase of unclean creeping things, and it shall be hidden from him; he also shall be unclean, and guilty.

3Or if he shall touch the uncleanness of man, whatever uncleanness it may be that a man shall be defiled with, and it be hid from him; when he knoweth of it, then he shall be guilty.