Midrash sa Deuteronomio 12:20: Devarim Rabbah, Midrash Tanchuma, Vayikra Rabbah & Sifra

“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.”

Another matter, “When [the Lord your God] will expand [your border]” – that is what the verse said: “I rejoice and am happy in Your kindness, for You have seen my affliction. You have known my soul’s distress, and You did not deliver me into the hand of the enemy; You set my feet in open space” (Psalms 31:8–9). The Rabbis say: This verse is speaking of Joseph. Joseph said: ‘Master of the universe, “I rejoice and am happy in Your kindness” that You performed with me. Had You exacted revenge on my behalf from Potifera’s wife, and had not given me the kingship, I would have rejoiced and been happy. Now that I have the kingship, “I rejoice and am happy in Your kindness….”’ “For You have seen my affliction” – this is Joseph, in whose regard it is written: “[He had sent a man before them, Joseph, who had been sold as a slave.] They tortured his legs with chains; his body was placed in irons” (Psalms 105:17–18). “You did not deliver me into the hand of the enemy” – this is Potifera. “You set my feet in open space” –You made me ruler over the entire land of Egypt. From where is this derived? As it is stated: “Joseph was the ruler over the land; he was the provider of grain to all the people of the land. Joseph's brothers came, and prostrated themselves to him, faces to the ground. Joseph saw his brothers, and he recognized them, but he acted as a stranger to them, and spoke harshly to them; he said to them: From where did you come? They said: From the land of Canaan, to acquire food” (Genesis 42:6–7).
Another matter, [the verse] “I rejoice and am happy in Your kindness” is speaking of Israel. Israel said: ‘Master of the universe, “I rejoice and am happy in Your kindness” that You performed with us. Had You exacted revenge against the Egyptians and not given us their wealth, we would have rejoiced. We have joy and happiness because You gave us their wealth.’ “For You have seen my affliction” – this is Israel, in whose regard it is written: “The Egyptians mistreated us, and afflicted us, and imposed upon us hard labor. We cried out to the Lord, God of our fathers, and the Lord heard our voice, and He saw our affliction…” (Deuteronomy 26:6–7). “You have known my soul’s distress” – this is Israel, in whose regard it is written: “They embittered their lives” (Exodus 1:14). “You did not deliver me into the hand of the enemy” – this is the wicked Pharaoh, as it is written: “The enemy said: I will pursue” (Exodus 15:9). “You set my feet in open space” – as you expanded my border, as it is stated: “When [the Lord your God] will expand [your border].”

“When the Lord your God will expand your border” – this is what the verse said: “A man’s giving expands for him, and will guide him before the great” (Proverbs 18:16). What is [the meaning of] “a man’s giving expands for him”? There was an incident involving Rabbi Eliezer and Rabbi Yehoshua who went out to collect for the matter of a mitzva for our rabbis.¹²They sought to collect donations to support the rabbis. They went to the environs of Antioch and there was a certain man there who was called Abba Yudan, who was accustomed to giving generously to our rabbis. That Abba Yudan had become poor. He saw that Rabbi Eliezer and Rabbi Yehoshua had come there to collect, and he concealed himself from them and entered his house. He spent a day there, and a second, and did not go down to the marketplace. His wife said to him: ‘Why did you not go down to the marketplace these two days?’ He said to her: ‘Our rabbis came to collect for the matter of a mitzva for those who toil in Torah. I do not have enough to give them and I am embarrassed to go down to the marketplace.’ His wife, who was very fond of mitzvot, said to him: ‘Do we not have one field remaining? Sell half of it and give [the money] to them.’ He went and he did so. He sold half of the field for five gold pieces and gave them to our rabbis. He said to them: ‘Pray on my behalf.’ They prayed on his behalf and said to him: ‘May the Omnipresent restore what you have lost.’ Our rabbis went on their way to collect elsewhere. That Abba Yudan plowed half the field and found a large hidden treasure. He became wealthier than he had been previously. When our rabbis were returning, they passed through that same place. They said to someone: ‘As you live, arrange a meeting for us with Abba Yudan.’ That man said to them: ‘Who can arrange a meeting – with the king and not with him.’¹³It is easier to meet the king than to meet with Abba Yudan. They said to him: ‘We seek only to ensure that he will not find out that we passed here and did not inquire after his wellbeing.’ Abba Yudan found out and came to them and gave them one thousand gold pieces. He said to them: ‘Your prayer bore fruit.’ They said to him: ‘We were aware of your good deeds and placed you at the head of the list.’ The Sages read in his regard: “A man’s giving expands for him, and will guide him before the great.”
Another matter, there was an incident involving Rabbi Ḥiyya, who held a fundraising campaign in the great study hall in Tiberias and a certain person pledged a litra of gold.¹⁴This was a very significant sum of money. Rabbi Ḥiyya took him, seated him next to him, and read in his regard: “A man’s giving expands for him [and will guide him before the great].”¹⁵Rabbi Ḥiyya was indicating that, just as the end of the verse had been fulfilled, as he had been seated among prominent people, he should fulfill the beginning of the verse, by making good on his pledge and giving generously (Etz Yosef).
Another matter, there was an incident involving Reish Lakish who went to Basra. There was a certain person there who was called Avin Ramaa. It is not that he was, God forbid, a swindler [ramai], but rather, he would employ cunning [merameh] regarding mitzvot. The entire congregation would pledge, and then he would pledge a sum corresponding to that of the entire congregation.¹⁶At first he would abstain from making any pledge, leading others to think he would not participate. Therefore they would pledge more money, so that the charity collection would meet its goals. Only afterward would he pledge as much as everyone else donated together. Alternatively, the people would know that he would match their donations and therefore they would pledge more, knowing that their donation would lead to even greater gain for the charity. Reish Lakish held a fundraising campaign there and he gave corresponding to the entire congregation. Reish Lakish took him, seated him next to him, and read in his regard: “A man’s giving expands for him, and will guide him before the great.” Rabbi Abahu said: Why do I need another place, derive it from its own place.¹⁷Why do I need to derive from a verse in Psalms that if someone gives charity generously he will be rewarded materially, when this can be derived from the Torah itself? What is written prior to it? “Beware lest you forsake the Levite” (Deuteronomy 12:19) and then, “when the Lord your God will expand your border, as He spoke to you.”¹⁸The juxtaposition of the verses indicates that if the Israelites take care of the Levites, who did not have ancestral property, God will expand their borders.