욥기 12:21의 미드라쉬

And Jacob called unto his sons (Gen. 49:1). Scripture states elsewhere in allusion to this verse: He removeth the speech of men of trust, and taketh away the sense of the elders (Job 12:20). This verse refers to Isaac and Jacob, for both of them desired to disclose the secrets of the Holy One, blessed be He. Concerning Isaac it is written: And he called Esau, his eldest son (Gen. 27:1), to reveal to him what was to transpire in the Messianic age. That was the reason the Holy One, blessed be He, withdrew the knowledge of it from him. Jacob likewise wanted to reveal to his sons what would occur in the Messianic age, as it is said: He called unto his sons and said: “Gather yourselves together that I may tell you” (ibid. 49:1).