Дварим 4:20 Мидраш: Mekhilta DeRabbi Yishmael, Kohelet Rabbah, Shemot Rabbah & Pirkei DeRabbi Eliezer

וְאֶתְכֶם֙ לָקַ֣ח יְהוָ֔ה וַיּוֹצִ֥א אֶתְכֶ֛ם מִכּ֥וּר הַבַּרְזֶ֖ל מִמִּצְרָ֑יִם לִהְי֥וֹת ל֛וֹ לְעַ֥ם נַחֲלָ֖ה כַּיּ֥וֹם הַזֶּֽה׃

Но вы взяли и вывели Господь из железной печи из Египта, чтобы быть для Него народом наследия, как и вы в этот день.

Mekhilta DeRabbi Yishmael

(Exodus 14:30) "and the L–rd saved Israel on that day": As a bird held in a man's hand, so that if he pressed its hand but a little he would choke it, as it is written (Psalms 124:6-8) "Our soul (at the splitting of the sea) escaped as from the hunter's snare. The snare broke and we escaped. Our help is in the name of the L–rd, Maker of heaven and earth." Or: As a man releasing a fetus from a cow's womb, as it is written (Devarim 4:34) "Or has a G–d ever done miracles to come and take for Himself a nation from the midst of a nation, etc."? Why "a nation from the midst of a nation"? — As a man releasing a fetus from a cow's womb, viz. (Ibid. 20) "and you did the L–rd take, and He brought you forth from the iron furnace, etc."

Kohelet Rabbah

“If the iron is dull, and one did not whet the edge, he must intensify his exertion; the advantage is in preparation with wisdom” (Ecclesiastes 10:10).
“If the iron is dull,” if the teacher’s face is dull toward his student like iron,50The teacher is not interested in expending energy to explain the material to his students. “and one did not [whet] the edge [panim],” and the teacher does not show the student a friendly countenance [panim], “whet [kilkal],” there is a deterioration [kilkul] in the actions of the student. “He must intensify his exertion” – what should [the student] do? He should bring ten people who will appease the teacher and, ultimately, he will have much preparation for wisdom.51He will be in a much better position to attain wisdom.
Another matter: “If the iron is dull,” if the student’s face is dull toward his teacher, as it is stated: “Iron sharpens iron; [so a man sharpens the countenance of his friend]” (Proverbs 27:17),52The teacher could be sharpened by the questions and insights of his student, but this student is dull and not insightful. and [therefore,] the teacher does not show the student a friendly countenance, “kilkal,” there is a deterioration [kilkul] in the actions of the student. “He must intensify his exertion” – [the student] should bring ten people who will appease his teacher. “The advantage [veyitron] is in preparation [hakhsheir] with wisdom” – ultimately, he will relinquish [motir] his anger and will enable [veyakhshir] him [to succeed in] his studies.
Another matter: “If the iron is dull,” if your studies have become dull like iron, “and one did not whet the edge,” [your teacher] cannot come to explain it to you, overcome it with your own ability.53If your teacher is no longer alive and you have unresolved questions, work hard to figure out the answers on your own (Etz Yosef).
One of the students of Rabbi Shimon ben Yoḥai forgot his studies. He went crying to the cemetery. As he was crying profusely, he was shown a dream, and [a voice] said to him: When you cast three pebbles at me I will come. That student went to an interpreter of dreams and recounted the incident to him. [The interpreter of dreams] said to him: ‘Recite your studies three times and it will come to you.’54Recite each thing you learn three times and you will remember it (Matnot Kehuna). He did so, and so it was for him.
Rabbi Berekhya said: If the nation whose power is as strong as iron, as it is written: “And the Lord took you and brought you out from the iron crucible, from Egypt” (Deuteronomy 4:20), becomes dull; “and one did not whet the edge” – and the Holy One blessed be He is not forthcoming toward the generation; “kilkal” – there are evil deeds in this generation. What shall they do? “He must intensify his exertion” – let them decree fasts, and the Holy One blessed be He will grant them eternal forgiveness.
Rabbi Ḥama bar Pappa said in the name of Rabbi Yehuda ben Rabbi Simon: If the skies above your heads have become dull like iron,55There is no rain. as it is stated: “I will render your skies like iron” (Leviticus 26:19), and the Holy One blessed be He is not forthcoming, there are corrupt [kilkal] actions in the generation. What shall they do? They shall decree a fast, and the Holy One blessed be He will provide relief to His world.

Shemot Rabbah

“Israel saw the great power that the Lord wielded upon Egypt and the people feared the Lord; and they believed in the Lord, and in His servant Moses” (Exodus 14:31).
“The people feared the Lord.” Our Rabbis taught: One who recites Shema is required to mention the splitting of the Red Sea and the plague of the firstborn in emet veyatziv,4Literally “true and firm,” these are the first words of the blessing recited after shema in the morning. but if he did not mention them, one does not require him to repeat it. However, if he did not mention the exodus from Egypt, one requires him to repeat it, as it is stated: “So you will remember the day that you departed from the land of Egypt” (Deuteronomy 16:3). What is the difference between the exodus from Egypt and the splitting of the Red Sea? It is that the exodus from Egypt was more difficult, as it is stated: “Or has any god attempted [to go and take a nation for him from the midst of another nation…according to everything that the Lord your God did for you in Egypt?] (Deuteronomy 4:34). “But the Lord has taken you…[from Egypt”] (Deuteronomy 4:20). Know that this is more difficult than that, as regarding the exodus from Egypt it is written: “I am the Lord your God [who took you out of the land of Egypt]” (Exodus 20:2), but regarding the splitting of the Red Sea, it does not mention the Name.5The fact that God says “I am the Lord your God who took you out of the land of Egypt” but does not say: “I am God who split the sea for you,” indicates that taking Israel out of Egypt was more difficult, and is a greater testament to God’s commitment to Israel.
Why must one mention the splitting of the Red Sea in emet veyatziv? It is because after He split the sea for them, they believed in Him, as it is stated: “And they believed in the Lord, and in His servant Moses.” Due to their belief, they were privileged to recite a song, and the Divine Spirit rested upon them, as it is written afterward: “Then Moses [and the Israelites] sang…” (Exodus 15:1). That is why a person must juxtapose redemption to prayer,6One should recite the Shemoneh Esrei prayer immediately after reciting the blessing mentioning the redemption from Egypt. just as they juxtaposed a song after their belief and the splitting. Just as they purified their hearts and recited a song, as it is written: “And the people feared the Lord; and they believed,” and then: “Then…sang,” so a person must purify his heart before he prays.
Likewise, Job said: “For there is no villainy in my hands, and my prayer is pure” (Job 16:17). Rabbi Yehoshua HaKohen ben Rabbi Neḥemya said: Is there a sullied prayer? Rather, anyone whose hands are sullied with robbery, he calls to the Holy One blessed be He and He does not answer him. Why? Because his prayer is [carried out] in sin, as it is stated: “God said to Noah: The end of all flesh [has come before me, as the earth is filled with villainy7This is understood as a reference to robbery. because of them]” (Genesis 6:13). But Job, who did not engage in robbery, his prayer was pure; that is why it says: “For there is no villainy in my hands.” Because there is no injustice in my hands or in my actions, my prayer is pure.
Rabbi Ḥama bar Rabbi Ḥanina said: From where is it derived that anyone with stolen property in his possession, his prayer is sullied? It is as it is stated: “When you spread your hands…I will not hear” (Isaiah 1:15). Why? It is because “your hands are full of blood” (Isaiah 1:15). From where is it derived that anyone who distances himself from robbery, his prayer is pure? It is as it is stated: “He who has clean hands, and a pure heart” (Psalms 24:4). What is written afterward? “He shall receive a blessing from the Lord…. This is the generation of those who seek Him” (Psalms 24:5–6).