"And they shall eat those things with which atonement was made" (Exodus 29:33). This teaches that the priests eat and the owners are atoned for. "And you shall burn the leftover in fire" (Exodus 29:34). Rabbi Simai said: do not let the verbal analogy [gezeira shava] be light in your eyes, for the law of "leftover" [notar] is one of the essentials of the Torah, and Scripture taught it only through a verbal analogy. What is the reason? It derives "holy," "holy": it is written here "and whoever eats it shall bear his iniquity, for he has profaned the holy thing of the LORD" (and so forth), and it is written there "and you shall burn the leftover in fire; it shall not be eaten, for it is holy." "It shall not be eaten, for it is holy." We learned there: piggul [an offering rendered invalid by improper intent] and notar [leftover] do not combine. Rav Yehudah said in the name of Shmuel: they taught this only regarding impurity of the hands, which is of rabbinic origin; but regarding eating they do combine. As it was taught, Rabbi Eliezer says: "it shall not be eaten, for it is holy": anything disqualified within what is holy, Scripture comes to place a prohibition upon eating it.
Burning the Leftover and the Power of the Verbal Analogy
Yalkut Shimoni on Torah 384:6
וְאָכְלוּ אֹתָם אֲשֶׁר כֻּפַּר בָּהֶם. מְלַמֵּד שֶׁהַכֹּהֲנִים אוֹכְלִים וּבְעָלִים מִתְכַּפְּרִין. וְשָׂרַפְתָּ אֶת הַנּוֹתָר בָּאֵשׁ. אֲמַר רַבִּי סִימַאי, אַל תְּהִי גְּזֵרָה שָׁוָה קַלָּה בְּעֵינֶיךָ, שֶׁהֲרֵי נוֹתָר אֶחָד מִגּוּפֵי תּוֹרָה וְלֹא לִמְּדוֹ הַכָּתוּב אֶלָּא בִּגְזֵרָה שָׁוָה. מַאי טַעְמָא יָלִיף קֹדֶשׁ "קֹדֶשׁ", כְּתִיב הָכָא "וְאֹכְלָיו עֲוֹנוֹ יִשָּׂא כִּי אֶת קֹדֶשׁ" וְגוֹ' וּכְתִיב הָתָם וְשָׂרַפְתָּ אֶת הַנּוֹתָר בָּאֵשׁ לֹא יֵאָכֵל כִּי קֹדֶשׁ הוּא. לֹא יֵאָכֵל כִּי קֹדֶשׁ הוּא. תְּנַן הָתָם. הַפִּגּוּל וְהַנּוֹתָר אֵין מִצְטָרְפִין. אֲמַר רַב יְהוּדָה אֲמַר שְׁמוּאֵל, לֹא שָׁנוּ אֶלָּא לְטֻמְאַת יָדַיִם, וּמִדְּרַבָּנָן הוּא, אֲבָל לְעִנְיַן אֲכִילָה מִצְטָרְפִין, דְּתַנְיָא, רַבִּי אֱלִיעֶזֶר אוֹמֵר, לֹא יֵאָכֵל כִּי קֹדֶשׁ הוּא, כָּל שֶׁבְּקֹדֶשׁ פָּסוּל בָּא הַכָּתוּב לִתֵּן לֹא תַעֲשֶׂה עַל אֲכִילָתוֹ.