Midras Keluaran 17:14: Tanna DeBei Eliyahu Rabbah, Mekhilta DeRabbi Yishmael, Pesikta DeRav Kahana & Eikhah Rabbah

One thing after another, the days were created, and not one of them is the seventh day forever, according to this world six thousand years, two thousand years, two thousand Torah, two thousand years, the son of David will die, and in our seasons many will go out, what went out, and will come in to work within two thousand years of the death of the son of David (more than 100 years) as it is said God did what he planned (Lamentations 2:17) and just as we make a shemitah once every seven years, so the Almighty will make a shemitah for the world one day which is a thousand years as it is said that a thousand years are in your eyes as yesterday (Psalms 90:4). And says And there was one day (Zechariah 14:7), this is the seventh day of the world, and at evening there was light (Zechariah 14:7), this is the world to come, which is said to be every month in its month, and every Sabbath in its Sabbath (Isaiah 66:23 ) And a psalm is said for the Sabbath day to the world that is all Sabbath. Another thing is a psalm a song for the Sabbath day that shuts off from the world. Another thing is a psalm a song for the Sabbath day is the seventh day to the world. And for the evening of the Sabbath it is the world to come in which there is no death for the eternal and the eternal, and in it there is neither sin nor iniquity nor plagues And no rebellions, but each and every one rejoices with his wisdom and understanding. How do you know that he did go out and learn from the Holy One, blessed be He, who rejoices in David in this world and the glory of heaven in the next world that was said and these are David's last words and ending "The utterance of is David the son of Ishai, and he utterance of the person who stands" on the mountains of learning, who accepted upon themselves the yoke of Torah and the yoke of mitzvot. What is your payment in front of Me? That you will be called 'the anointed of the God of Yaakov, and the sweet singer of Israel'. Happy is the person who sets themselves as an ox to the yoke, and as a donkey to the burden, and sits and meditates every day in Torah, always, immediately the Spirit of God rests on them, and the their Torah gets inside them, as it is written "Ho, everyone who thirsts, come for water" (Isaiah 55:1), and any mention of water really means Torah. How so? Explanation: a person reads Torah, prophets, writings, Mishnah, Halakhot, Agadot, and Midrash; and spends much time sitting, and little time in business, immediately the spirit of God is within that person, and His message are in that person's tongue, as it is written "The spirit of Ad-nai has spoken through me, His message is on my tongue" (II Sam 23:2). Happy is the person that plays with the words of the Torah and sits and chews on them like an animal that chews the cud on the field. ...

(Exodus 17:14) "And the L–rd said to Moses: Write this as a remembrance in the book and place it in the ears of Joshua": The early elders said: So is it with all the generations. The rod with which Israel is smitten, in the end, will be smitten itself. Let all men learn from Amalek, who came to smite Israel, and whom the Holy One Blessed be He "smote" out of this world and the world to come. As it is written (Ibid.) "for blot out will I blot out the remembrance of Amalek." And thus, the wicked Pharaoh, who subjugated Israel — the Holy One Blessed be He drowned him in the Red Sea, viz. (Psalms 136:15) "And He shook out Pharaoh and his hosts in the Red Sea." And thus, every people and kingdom that arises to harm Israel will be harmed in the same manner. "As one metes it out, so is it meted out to him," viz. (Exodus 18:11) "for (they were destroyed) by the (very) thing (water) whereby they devised evil against them."

(Exodus 17:14) "For erase shall I erase": "erase" — in this world; "shall I erase" — in the world to come. "the remembrance" — Haman; "Amalek" — as stated. Variantly: "erase" — him and his descendants; "shall I erase" — him and his families. These are the words of R. Yehoshua.