Néhémie 9:13 Midrash : Shemot Rabbah & Midrash Tehillim

Rabbi Levi said: If Israel observes Shabbat properly, even one day, the son of David²⁵The Messiah. will come. Why? Because it is equivalent to all the mitzvot. Likewise it says: “For He is our God, and we are the people of His pasture and the flock of His hand; today, would you only heed His voice” (Psalms 95:7). Rabbi Yoḥanan said: The Holy One blessed be He said to Israel: ‘Even though I set a limit for the end, and it will come whether they repent or do not repent, it will come only at its time. If they repent, even one day, I will bring it not at its appointed time. That is, “today, would you only heed His voice.” Just as we saw that for all the mitzvot, the son of David comes, for the observance of one day of Shabbat, the son of David comes, because Shabbat is equivalent to all mitzvot.
Rabbi Elazar bar Avina said: We find in the Torah, in the Prophets, and in the Writings that Shabbat is equivalent to all the mitzvot. In the Torah, from where is it derived? From the fact that when Moses forgot to tell them the mitzva of Shabbat, the Holy One blessed be He said to him: “Until when do you refuse to observe My commandments…” (Exodus 16:28). What is written thereafter? “See that the Lord has given you the Shabbat” (Exodus 16:28). In the prophets, from where is it derived? From that which is stated: “The house of Israel defied Me in the wilderness, they did not follow My statutes” (Ezekiel 20:13). What is written thereafter? “They desecrated My Shabbats” (Ezekiel 20:13). In the Writings, from where is it derived? From that which is stated: “You came down upon Mount Sinai and spoke to them [from heaven and gave them upright ordinances and laws of truth, good statutes and mitzvot]” (Nehemiah 9:13). What is written thereafter? “You informed them of Your holy Shabbat” (Nehemiah 9:14). The Holy One blessed be He said to Israel: ‘If you merit to observe Shabbat, I consider it for you as though you observed all the mitzvot of the Torah. If you desecrate it, I consider it for you as though you desecrated all the mitzvot.’ Likewise, it says: “Who keeps the Shabbat from its desecration and prevents his hand from performing any evil” (Isaiah 56:2).
When a person observes the Shabbat, he issues a decree and the Holy One blessed be He fulfills it, as it is stated: "If you restrain your walking because of the Sabbath” (Isaiah 58:13). What is written thereafter? “Then you will delight in the Lord” (Isaiah 58:14), just as it says: “Delight in the Lord, and He will grant you the desires of your heart.” (Psalms 37:4). Moreover, everything that you eat in this world is only from the profits, but the principal remains for the World to Come, as it is stated: “I will feed you the inheritance of Jacob your forefather, for the mouth of the Lord has spoken” (Isaiah 58:14).

"You are righteous, O Lord, etc." Solomon said (Proverbs 8:8-9), "In righteousness, all the words of my mouth are just; none of them is crooked or perverse. All of them are clear to the perceptive, etc." What is meant by "In righteousness, all the words of my mouth"? Everything that the Lord has spoken from His mouth in righteousness, they are righteous and upright. Therefore it is said, "You are righteous, O Lord, and Your judgments are upright." Just as You are righteous, so are Your judgments righteous and upright. And it is also said (Deuteronomy 4:7), "For what great nation is there that has God so close to them, etc." And so the Assembly of Israel said (Nehemiah 9:13), "And You descended upon Mount Sinai and spoke with them from heaven, and gave them just ordinances, etc." Therefore it is said, "You are righteous, O Lord, etc." "You have commanded righteousness in Your testimonies." What is meant by "You have commanded righteousness"? The Lord acted righteously with Israel by giving them the Torah. And it is also said (Deuteronomy 6:24), "And the Lord commanded us to do all these statutes, to fear the Lord our God, etc." What is written after it? "And it will be righteousness for us if we are careful to do all these commandments before the Lord our God, etc." Therefore it is said, "You have commanded righteousness in Your testimonies." "What is faith? Great faith is the Torah, in which the Lord created his world and swore by it, as it is said (Psalm 89:3): "Where are your former mercies, O Lord, which you swore to David in your faithfulness?" Therefore, the Torah is called "very faithful". (Psalm 119:139) "My zeal has consumed me," etc. David said, "I am not jealous of the food and drink of the wicked, but I am jealous of all the good that you bring upon them, and how they have forgotten your Torah." And likewise it says (Lamentations 3:17): "You have removed peace from my life," etc. Therefore it is said, "For they have forgotten your word, my enemy." (Psalm 119:139) "Your word is very pure," etc. What is meant by "very pure"? A parable: To what is this matter comparable? To a king who had a bowl of silver. He gave the silver to a refiner and said to him, "Refine it for me." He put it in the crucible, refined it, and took it out. He said to him, "Refine it again." He refined it a second time, and a third time. So too, the Holy One, blessed be He, refined the Torah 49 times. And it says (Proverbs 30:5), "Every word of God is pure." And it says (Psalm 12:7), "The words of the Lord are pure words," etc. Thus, the Torah is interpreted in 49 ways. Therefore it is said (Proverbs 30:5), "Every word of God is pure." And it says, "Your word is very pure."