וְאִם־נֶ֙פֶשׁ֙ כִּ֣י תֶֽחֱטָ֔א וְעָֽשְׂתָ֗ה אַחַת֙ מִכָּל־מִצְוֺ֣ת יְהוָ֔ה אֲשֶׁ֖ר לֹ֣א תֵעָשֶׂ֑ינָה וְלֹֽא־יָדַ֥ע וְאָשֵׁ֖ם וְנָשָׂ֥א עֲוֺנֽוֹ׃
A jeżeliby kto zgrzeszył, a wykroczył przeciw któremu ze wszystkich przykazań Wiekuistego, wzbraniających cokolwiek czynić, a nie wiedział, i stał się winnym, i tak uniósł na sobie winę swą:
Rashi
ולא ידע ואשם … והביא [AND IF A SOUL SIN, AND DO ANY OF THESE THINGS WHICH SHOULD NOT BE DONE …] AND HE DOES NOT DISCOVER THAT HE IS GUILTY … HE SHALL BRING [A RAM … FOR A GUILT OFFERING] — This paragraph (vv. 17—19) is speaking of a person to whom there has occurred a כרת ספק (i. e. it is speaking of a person who is doubtful whether he has inadvertently committed an act of such a character as to be punishable with כרת if done willfully), and he does not know whether he has actually committed a sinful act or not. For instance: חלב (fat forbidden to be eaten under the penalty of כרת) and permitted fat (שומן) lay before him, and he believed that both were permissible food (i. e. that both were שומן), and he ate one of them. Afterwards, however, people told him that one of these was חלב, but he does not know whether he had eaten that which was חלב. Then such a one has to bring an אשם תלוי (the guilt-offering for a doubtful sin, lit., the guilt-offering in suspense, from תלה to “be in suspense”); and this protects him against punishment so long as he does not become cognisant that he has undoubtedly sinned, and if he becomes cognisant of this after a time he has to bring a sin-offering (cf. Keritot 22b, 23a).
Kli Yakar
And he did not know, and he is guilty, and he shall bear his iniquity. Rabbi Yose the Galilean says: Scripture punishes one who did not know, all the more so one who did know. Rabbi Yose says: If you wish to know the reward for commandments, go and learn from Adam the first man, etc… One who refrains from eating forbidden foods [pigulim], and from leftovers [notarot], and one who fasts on Yom Kippur, etc. (Torat Kohanim, Leviticus 363). One must contemplate why specifically these three were mentioned. It appears that since Adam the first man stumbled by eating something forbidden, therefore Rabbi Yose mentioned the opposite — one who is careful regarding forbidden food has three levels: First, “One who refrains from forbidden foods [pigulim]” is an all-encompassing term for abstaining from any forbidden food, for it is pigul. And not only does such a person refrain from eating forbidden food like Adam the first man did, but second, even from what is permitted, they only eat what is necessary and distance themselves from leftovers [notar], not consuming any luxury [motarot] beyond what is necessary. For the righteous person only eats to satisfy their soul for bodily sustenance alone. Third, not only does such a person refrain from luxuries, but even from necessities they distance themselves at times — referring to one who fasts on Yom Kippur in order to purify their material being in the crucible of affliction, how much more so will they be rewarded. And from eating, you can make comparisons to other human activities and needs. The reason Rabbi Yose connected his words to this passage, it seems to me, is to explain why the verse says he is guilty, he shall surely be guilty [asham hu, ashom asham] to the Lord — why these three mentions of guilt? It comes to teach that if one is guilty for eating forbidden food [pigul], all the more so would they be guilty for eating luxuries of permitted food, and all the more so will they not fast. From this, you can learn what reward awaits one who is careful in all three areas.
Sforno
ואשם ונשא עונו, our sages have a tradition that the Torah here speaks of an asham taluy, a guilt offering offered while the exact nature of the guilt is unclear. The person offering it is not even sure that he is guilty of an offence. Considering this state of affairs the Torah writes ונשא עוונו, he carries (the burden) of his guilt. The guilt is not spelled out precisely as it is not yet known. He may not actually have committed a sin, but this does not mean that he is free from guilt as had he been careful he would never have been in the predicament of not knowing if he had committed the specific sin he is afraid he might have committed.