Negative commandment · Lo Ta’aseh #132 of 613
Not to eat piggul
שלא לאכול פיגול
The verse · Vayikra 7:18
וְאִם הֵאָכֹל יֵאָכֵל מִבְּשַׂר־זֶבַח שְׁלָמָיו בַּיּוֹם הַשְּׁלִישִׁי לֹא יֵרָצֶה הַמַּקְרִיב אֹתוֹ לֹא יֵחָשֵׁב לוֹ פִּגּוּל יִהְיֶה וְהַנֶּפֶשׁ הָאֹכֶלֶת מִמֶּנּוּ עֲוֺנָהּ תִּשָּׂא
“And if any of the flesh of the sacrifice of his peace offering be eaten at all on the third day, it shall not be accepted, neither shall it be imputed to him who offers it: it shall be an abomination, and the person that eats of it shall bear his iniquity.”
The Rambam’s words
Not to eat piggul, as [Leviticus 7:18] states: "It will not be accepted for him. Instead, it will be considered as piggul. Any person who eats it will bear his guilt." This sin is punishable by karet.
שלא לאכול פיגול, שנאמר "המקריב אותו לא ייחשב לו, פיגול יהיה; והנפש האוכלת ממנו, עוונה תישא" (ויקרא ז,יח); והוא בכרת.
Why · Sefer HaChinuch #144
To not eat piggul
“From the roots of this commandment is the foundation that we have built at first — as we have said that the matter of the sacrifice is to refine the thoughts of people; and through the acts in their hands to fashion in their souls the evil of sin and the good of straight paths.”
Who & when
“And the prohibition of eating piggul is practiced at the time of the [Temple] by males and females — even Israelites, as the Torah prohibited it in general, whether to priests or whether to Israelites.”
Where in the Mishneh Torah
Hilchot Sacrifices Rendered Unfit הלכות פסולי המוקדשין