Midrash su Genesi 15:14

Before the world was created, the Holy One, blessed be He, with His Name alone existed, and the thought arose in Him to create the world. He began to trace (the foundations of) the world before Himself, but it would not stand. They told a parable, To what is the matter like? To a king who wishes to build a palace for himself. If he had not traced in the earth its foundations, its exits and its entrances, he does not begin to build. Likewise the Holy One, blessed be He, was tracing (the plans of) the world before Himself, but it did not remain standing until He created repentance.

Reuben, Simeon, and all the other tribes were mentioned because of the future redemption of Israel. Reuben: I have surely seen the affliction of my people (Exod. 3:7). Simeon: And God heard their groaning (ibid. 2:24). Levi: Many nations will attach themselves to the Lord (Zech. 2:15). Judah: I will give thanks unto Thee, O Lord, for though Thou wast angry with me, Thine anger is turned away and Thou comfortest me (Isa. 12:1). Issachar: For thy ways shall be rewarded (Jer. 31:16). Zebulun: I have surely built thee a house of habitation (I Kings 8:13). Benjamin: The Lord hath sworn by His right hand (Isa. 62:18). Dan: And also that nation, whom they shall serve, will I judge (Gen. 15:14). Naphtali: Thy lips, O my bride, drop honey (Song 4:11). Gad: Now the manna was like coriander seed (Num. 11:7). Asher: And all the nations shall call you happy (Mal. 3:12). Joseph: The Lord will set His hand again the second time (Isa. 11:1).

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