Charles Ellicott Commentary Leviticus 5:17

"And if any one sin, and do any of the things which Jehovah hath commanded not to be done; though he knew it not, yet is he guilty, and shall bear his iniquity." — Leviticus 5:17 (ASV)

And if a soul sin. —To guard the Israelites most effectively against making profane use of anything dedicated to the sanctuary and its service, it is further enacted here in Leviticus 5:17-19, that a trespass offering is to be brought when a man only suspects that he had used things which belonged to the Lord, though he can no longer remember what particular holy property it was, which he used for his own purpose. In the canonical exposition, which prevailed during the Second Temple, of these sacrificial laws, the trespass offering enacted here is called “The Doubtful Offering,” in contrast to the one enacted in Leviticus 5:14-16, which is called “The Certain Offering.”

These things. —That is, the holy things of the Lord specified in Leviticus 5:15.

Though he wist it not, i.e., is uncertain about it. Thus, for instance, he might be in doubt whether or not his transgression consisted in not delivering the first-fruit to the sanctuary, or in having used some other sacred property. (Compare Genesis 20:5 and following; 2 Samuel 20:1 and following.)

Yet is he guilty, and shall bear his iniquity.—Still, he feels that he may be guilty of the transgression, and consequently is burdened with the weight of his iniquity. (See Leviticus 5:1.)