Leviticus 5:17-19 (KJV)
17 And if a soul sin, and commit any of these things which are forbidden to be done by the commandments of the Lord; though he wist it not, yet is he guilty, and shall bear his iniquity.
18 And he shall bring a ram without blemish out of the flock, with thy estimation, for a trespass offering, unto the priest: and the priest shall make an atonement for him concerning his ignorance wherein he erred and wist it not, and it shall be forgiven him.
19 It is a trespass offering: he hath certainly trespassed against the Lord.
Leviticus 5
The Trespass Offering
It is important to find out when we have sinned against God. To be confronted about these sins is necessary.