Дварим 12:15 Мидраш: Devarim Rabbah & Sifrei Devarim

“When the Lord your God will expand your border, as He spoke to you, and you will say: I will eat meat, because your heart will desire to eat meat; with all your heart’s desire, you may eat meat” (Deuteronomy 12:20).
“When the Lord your God will expand…” Halakha: is it permitted for a person of Israel to cover the blood of slaughter on a festival?⁸Upon slaughtering birds or undomesticated animals, one is required to cover the blood with dirt (Leviticus 17:13). This is what the Sages taught: One who slaughters an undomesticated animal or a bird on a festival, Beit Shammai say: He digs with a shovel and covers the blood. Beit Hillel say: He may slaughter only if he had earth prepared.⁹Mishna Beitza 1:2. Rabbi Ḥagai said in the name of Rabbi Aḥa: One who does not have earth prepared should not slaughter. Why? Because the difference between Festivals and Shabbat is only preparing food alone.¹⁰Mishna Megilla 1:5. The only difference between the prohibition of labor on Shabbat and Festivals is the dispensation to perform certain actions on Festivals in the course of food preparation. Covering the blood is not directly connected to food preparation, and therefore digging dirt in order to cover the blood would be prohibited on a Festival. Therefore, if one slaughtered on a festival, one must have earth prepared to cover it with.
Rav Bisena said in the name of Rav Aḥa: Come and see, the Holy One blessed be He said: ‘What I prohibited for you in a domesticated animal, I permitted for you in an undomesticated animal…until [I permitted all of them] in fish.’¹¹The reference is to a statement cited in full elsewhere: “I prohibited the fat of a domesticated animal for you, but I permitted it for you in an undomesticated animal. I prohibited the sciatic nerve for you in an undomesticated animal, but I permitted it for you in birds. I prohibited for you birds without slaughter, but I permitted fish for you” (see Vayikra Rabba 22:10; Ḥullin 109b). The Rabbis said: There are many matters that the Holy One blessed be He prohibited and then permitted them elsewhere. Know that the Holy One blessed be He prohibited slaughtering and eating [an animal] until one brings it to the Tent of Meeting [as an offering]. From where is this derived? As it is stated: “[If anyone…offers a burnt offering or a sacrifice], and to the entrance of the Tent of Meeting does not bring it, to present it to the Lord, that man shall be excised from his people” (Leviticus 17:8–9). What [else] is written there? “And he did not bring it to the entrance of the Tent of Meeting, to present an offering to the Lord before the Tabernacle of the Lord, it will be accounted as blood for that man; he has shed blood, and that man shall be excised from among his people” (Leviticus 17:4). But He then permitted it to them here, as it is stated: “Only, with all of your heart’s desire, you may slaughter and eat meat in accordance with the blessing of the Lord your God that he gave you within all your gates, the impure…” (Deuteronomy 12:15). From where is it derived? From what we read here: “When the Lord your God will expand your border.”

“And you will say: I will eat meat, because your heart will desire to eat meat; with all your heart’s desire, you may eat meat” – this is what the verse said: “Who performs justice for the oppressed, gives bread to the hungry; the Lord releases the imprisoned” (Psalms 146:7) – it is speaking of Israel. Rabbi Pinḥas bar Ḥama said: It teaches that there were more than seventy nations in Egypt, and of all of them, they enslaved only Israel. Who executed justice on their behalf? He “who performs justice for the oppressed.” “Gives bread to the hungry” – this is Israel. From where is this derived? As it is stated: “He afflicted you, and starved you, and fed you the manna that you did not know and your fathers did not know, in order to impart to you that man does not live by bread alone; rather, it is by everything that emanates from the mouth of the Lord that man lives. Your garment did not grow worn from upon you and your foot did not swell these forty years. And you shall know in your heart, that, as a man chastises his son, so the Lord your God chastises you” (Deuteronomy 8:3–5). “The Lord releases the imprisoned [matir asurim]” – these are Israel. How so? The Rabbis said: The Holy One blessed be He prohibited eight matters for them and permitted eight of them. The Holy One blessed be He said: ‘I prohibited fats for you…until cloaks with ritual fringes.’¹⁹The full version of this passage is found in Vayikra Rabba (22:10): “I prohibited for you menstrual blood; I permitted for you hymenal blood. I prohibited for you a married woman; I permitted for you a captive woman. The brother’s wife [is forbidden], I permitted for you a levirate wife. A woman and her sister, [which is forbidden] during their lifetimes, I permitted for you after death. Wearing diverse kinds [is forbidden], I permitted for you a linen garment with ritual fringes. The flesh of a pig, I permitted for you a fish called shibuta. Animal fat [ḥelev], I permitted for you animal fat [shuman].” That is, “the Lord releases the imprisoned [matir asurim].”²⁰This is expounded in the sense of “permits [matir] prohibitions [isurim].” So, too, elsewhere He prohibited meat of desire [taava]²¹He prohibited slaughtering and eating an animal without bringing it as an offering. and here, he permitted it for them. From where is it derived? “Only, with all of your heart’s desire [avat], you may slaughter and eat meat” (Deuteronomy 12:15).

(Devarim 12:15) "Only with all the desire of your soul shall you slaughter": Of what is Scripture speaking here? If of "lust-flesh" (i.e., slaughtering a non-consecrated animal for food), this is spoken of elsewhere (20); and if of the eating of consecrated flesh, this has already been spoken of (as being permitted only in Jerusalem, whereas here it is written "in all of your gates"). It must be speaking, then, of consecrated animals (which had sustained a blemish) and were redeemed (and were to be eaten in "all of your gates").