Midrash su Genesi 30:17

R. Chelbo again questioned R. Samuel b. Nachmeni: "It is written (Gen. 30, 25) And it came to pass, when Rachel had borne Joseph, etc. Why when Joseph was born?" And he answered: "Because Jacob our father saw that the descendants of Esau would become submissive only to the descendants of Joseph, as it is said (Oba. 1, 18) And the house of Jacob shall be a fire, and the house of Joseph a flame, and the house of Esau stubble." R. Chelbo objected to him from (I. Sam. 30, 17) "And David smote them from the twilight even unto the evening of next day," etc. (Hence we see that they were submissive also to David, who was a descendant of Judah, and not of Joseph). Samuel answered: "The one who made you read the prophets did not read with thee Hagiographa, in which it is written (I Chron. 12, 21) And as he was going over to Ziklag… . captains of the thousands that belonged to Manasseh." [Hence they were submissive to the descendants of Joseph]. R. Joseph objected from (Ib. 4, 42, 43) And some of them, even of the sons of Simeon, five hundred men, went to Mount Seir, having at their head Pelatiyah and Nearyah and Rephayah, and Uzzie, the sons of Yishi. And they smote the rest of the Amalekites that had escaped, and dwelt there unto this day. Rabba b. Shila thereupon said: "Yishi was a descendant of Manasseh, as it is written (Ib. 5, 24) and the children of Manasseh were Epher and Yishi."