Or HaChaim on Leviticus 22:16/אור החיים על ויקרא כ״ב:ט״ז

1 והשיאו אותם עון אשמה, "and so cause them to bear the sin which brings guilt, etc." The meaning of the verse is that if the guilty person did not make restitution of both the value of the amount of holy things consumed plus the 20%, the parameter of the sin will grow wider so that it will be classified as if it had been committed intentionally (i.e. עון). The justification for this is that when one fails to correct a sin inadvertently committed although one has been given an opportunity to correct it, the original sin becomes so much more serious. The word והשיאו is equivalent to ינשאו "they will have to bear them;" הם i.e. the combined sins. The Torah adds: באכלם את קדשיהם, the sin will now be considered not merely failure to pay the penalty but it will be considered as if they had eaten their holy things on purpose. Compare my comments on the last verse.