Берешит 18:18 Мидраш: Midrash Tehillim, Midrash Tanchuma, Ein Yaakov (Glick Edition) & Bereshit Rabbah

"To the conductor, to the rivers. Rabbi Samuel bar Nahmani said about two rivers, which David inherited the kingship in this world and in the world to come. David said about both of them, "I sing to the rivers." Rabbi Joshua ben Levi said that the rivers are an acronym for the five books of the Torah. Fifty corresponds to the fifty days between Passover and Shavuot. Eight corresponds to the eight days of circumcision. Ten corresponds to the Ten Commandments. Thirty corresponds to the thirty righteous people whom the world cannot do without, like Abraham, as it is written, "Abraham will surely become a great and mighty nation" (Genesis 18:18). In the numerology, "great and mighty nation" adds up to thirty. When Israel merits eighteen in the Land and twelve outside the Land, it is a good sign for Israel when the Land has twelve righteous people. Rabbi Zeira said, "The conversation of Israel is Torah. Let it be a sister to seven and a mother to eight." Rabbi Joshua ben Levi said that this refers to Abraham, who was a father to Isaac, Ishmael, and the sons of Keturah. Rabbi Samuel said that this refers to Jesse, who was a father to eight. And "a sister to seven" refers to David, who was a brother to seven, as it is written, "Incline Your ear to me and answer me" (Psalms 86:1). This refers to David's tribe, which was given the attribute of hearing, as it is written, "Hear, O Lord, the voice of Judah" (Deuteronomy 33:7). "For I am poor and needy" (Psalms 86:1). Rabbi Yochanan said that wherever it says "poor and needy" in Israel, the verse is speaking about the poor and needy, as it is written, "the poor and needy" (Isaiah 41:17)." David said before the Lord, the Master of the Universe: "When I have the strength to stand before You in prayer and utter my words, listen to me. But when I lack the strength, let me reflect on my thoughts and meditate. Another verse says, 'For I am poor and needy' (Psalm 86:1). Was David poor? The verse in Chronicles (1 Chronicles 22:14) says, 'In my distress, I prepared for the house of God.' What does 'my distress' mean? It refers to the suffering that I endured. Rabbi Yehuda interpreted this in four kingdoms. 'Utter my words' refers to Babylon, 'meditate' refers to Media, 'listen to my voice' refers to Greece, and 'heed my plea' refers to Edom. Why does it say 'my kings and my God' in Edom? Israel said before the Lord, 'See how many decrees and laws she imposes on me to nullify Your divinity and kingship, but I will not abandon them.' Every day we enter synagogues and acknowledge You as King twice, saying, 'Hear, O Israel, the Lord our God, the Lord is One,' and we declare that we serve You. As it says, 'My beloved is mine, and I am his' (Song of Songs 2:16)."

Now Jacob saw that there was grain in Egypt (Gen. 42:1). Scripture says elsewhere in allusion to this verse: I have been young, and now am old; yet have I not seen the righteous forsaken, nor his seed begging bread (Ps. 37:25). R. Samuel the son of Nahman said: This verse was spoken by the Prince of the Universe.³God appointed Enoch the prince of angels. See Ginzberg, Legends of the Jews 1:129. I have been young: from the time of Adam; Now am old: until the days of the Messiah; yet have I not seen indicates that there is no time in which the Holy One, blessed be He, permits the world to be without righteous ones. In fact righteous men appear in every generation, as R. Tanhuma explained in the name of R. Aha: The world never lacks thirty men as righteous as Abraham, as it is said: And Abraham shall surely become a great nation (Gen. 18:18). The numerical value of the Hebrew letters of the word shall become (yihyeh) adds up to thirty.

R. Levi said: He is the one concerning whom the Holy One, blessed be He, said: All the nations of the earth shall be blessed through him (Gen. 18:18). During the generation of the separation, the sea inundated the world and the descendants of Ham were scattered (as thirty families), as it is said: The Lord scattered them abroad (Gen. 11:8). But now, the Holy One, blessed be He, said to him: I will cause them to descend from you, as it is said: All the nations of the earth will be blessed through him. He begot the (thirty) families, and these are they: the twelve princes that descended from Ishmael (ibid. 25:12—16), the sixteen offspring from his wife Keturah (ibid., vv. 1—4), and the two nations in the womb of Rebecca (ibid., v. 23). Hence Scripture says: All the nations of the earth will be blessed through him.