Rabbi Hiyya says: from where do we learn that slaughter is from the neck? As it is written, "And the sons of Aaron the priests shall arrange the pieces" (Leviticus 1:8) - since there is no need for Scripture to say "the head and the fat," for were not the head and the fat included among all the pieces? Why then is it stated? Because it is said, "And he shall flay the burnt offering and cut it into its pieces" - I have only the pieces that are included in the flaying; from where do I include the head, which had already been severed? Scripture teaches, saying "and its head and its fat, and he shall arrange" (Leviticus 1:12). Since it says "the head, which had already been severed," it follows that slaughter is from the neck. The Sage opened with "head and fat" and concluded with "its head and its fat." This is what he means: from where to include the head, which had already been severed? Scripture teaches, saying "the head and the fat." And why do I need "its head and its fat"? It is needed for what was taught: from where that the head and the fat precede all the other pieces? Scripture teaches, saying "its head and its fat, and he shall arrange." And the first "fat" that the Merciful One wrote, why do I need it? For what was taught: how does he do it? He drapes the fat over the place of slaughter and brings it up, and this is the way of honor toward Heaven.
Slaughter From the Neck and Covering the Wound in Honor
Yalkut Shimoni on Torah 444:1
רַבִּי חִיָּא אוֹמֵר מִנַּיִן לִשְׁחִיטָה מִן הַצַּוָּאר, דִּכְתִיב (להלן פסוק ח) "וְעָרְכוּ בְּנֵי אַהֲרֹן הַכֹּהֲנִים אֵת הַנְּתָחִים", שֶׁאֵין תַּלְמוּד לוֹמַר "אֶת הָרֹאשׁ וְאֶת הַפָּדֶר", וַהֲלֹא רֹאשׁ וָפֶדֶר בִּכְלַל כָּל הַנְּתָחִים הָיוּ, וְלָמָּה נֶאֱמַר, לְפִי שֶׁנֶּאֱמַר "וְהִפְשִׁיט אֶת הָעוֹלָה וְנִתַּח אֹתָהּ לִנְתָחֶיהָ" אֵין לִי אֶלָּא נְתָחִים שֶׁיֶּשְׁנָן בִּכְלַל הַפְשָׁטָה מִנַּיִן לְרַבּוֹת אֶת הָרֹאשׁ שֶׁכְּבַר הֻתַּז, תַּלְמוּד לוֹמַר (להלן פסוק יב) "וְאֶת רֹאשׁוֹ וְאֶת פִּדְרוֹ וְעָרַךְ" מִדְּקָאָמַר אֶת הָרֹאשׁ שֶׁכְּבָר הֻתַּז, מִכְּלָל דִּשְׁחִיטָה מִן הַצַּוָּאר תַּנָּא פָּתַח בְּרֹאשׁ וָפָדֶר, וּמְסַיֵּם (להלן פסוק יב) בְּ"רֹאשׁוֹ וּפִדְרוֹ" הָכִי קָאָמַר מִנַּיִן לְרַבּוֹת אֶת הָרֹאשׁ שֶׁכְּבָר הֻתַּז, תַּלְמוּד לוֹמַר "אֶת הָרֹאשׁ וְאֶת הַפָּדֶר". וְ"רֹאשׁוֹ וּפִדְרוֹ" לָמָּה לִי, מִיבָּעֵיהּ לִי לְכִדְתַנְיָא מִנַּיִן לְרֹאשׁ וָפָדֶר שֶׁקּוֹדְמִין לְכָל הַנְּתָחִים תַּלְמוּד לוֹמַר "רֹאשׁוֹ וּפִדְרוֹ, וְעָרַךְ" וּ"פָדֶר" קַמָּא דְּכָתַב רַחֲמָנָא לָמָּה לִי לְכִדְתַנְיָא כֵּיצַד הוּא עוֹשֶׂה, חוֹפֶה הַפֶּדֶר עַל בֵּית הַשְּׁחִיטָה וּמַעֲלֵהוּ וְזֶהוּ דֶּרֶךְ כָּבוֹד שֶׁל מַעְלָה.