Well, perhaps he could have children with another wife, but those children, like Abraham’s later children, would not have been included in the covenant. It would mean that not all of his children would be included in Brit Avot, which was a perfectly reasonable conclusion. Indeed, it was this conclusion that his father and grandfather ultimately drew, though neither without a ‘fight’. Thus, Jacob arrives at a moment in his life where he is ready, like his father and grandfather, to ‘retire’ from the covenant business. After choosing successors, each of them returned to ‘civilian’ life, which passes without incident, and in prosperity. Recall that this was built into the ‘Brit Bein Habetarim’ – that Abraham was promised that he would be a ger from the moment Yitzchak is born, but that at the end of his life he would enjoy his old age. None of the Avot were able to truly ‘enjoy life’ as long as they bore the Abrahamic covenant. They were destined to wander (la-gur).
Thus, at this point in the story, Jacob wishes to ‘retire’. He will elect a successor and then retire from the Covenant business. The first verse says it all – VA-YESHEV Yaavov be-eretz MEGUREI aviv… Jacob SETTLED in the land of his fathers’ SOJOURN. and Rashi comments, so perfectly and succinctly ‘bikesh Yaakov la-shevet be-shalvah’ – Jacob wished to dwell in tranquility. He chose Joseph and retired, thinking he’d live out his days happily. Boy was he wrong.
As a sign of his choice, Jacob gives Joseph the ‘striped coat’ to wear. His brothers hate him and are unable to speak with him. Understandable. Then come the dreams, and they get jealous. The dreams weren’t just about the covenant, the content of ‘Brit Avraham’. They were about earthly domination. They were rooted in the brachot that Jacob wrested from Esau – the blessings of the fat of the land, power, and sovereignty over brothers. Here, already, they had grounds (and precedent) to believe that Dad got the wrong guy. They may have been able to live with one being the covenant-bearer. They couldn’t bear his earthly domination as well. And they therefore decide to put an end to his illusions. As for their father, he’d simply have to pick again.
Jacob, for whatever reason, didn’t think so. When he learns of Joseph’s ‘death’, he is unconsolable. He felt that his own future died with Joseph, and that the covenantal lineage would end there. Note that until Jacob learns that Joseph is alive in Vayigash(45:26-46:4), the covenantal story goes cold. The way Rashi alerts us to this is by saying that Jacob lost his ‘ruach ha-kodesh’ – his Divine spirit.
At the point in the story where Joseph is gone, what does everyone think? At what point does it dawn on anyone that maybe they are ALL covenant-bearers, that maybe Jacob was mistaken about the NEED to choose a single successor. There’s only evidence for two brothers, and it’s the process by which those two brothers are ‘reunited’ to the Israelite family which frames the story until the actual reunion. The two brothers are Joseph and Judah.
Joseph, obviously, was a tougher sell. It’s unclear, beginning to end, what Joseph’s ‘plan’ was with the brothers, but one thing seems clear. HE DIDN’T WANT TO GO BACK TO HIS FATHER’S FAMILY. And why would he? They sold him! Was Dad in on it? Maybe. Either was, he wants to move on. He gets married to a local girl (who the Midrashim again, amazingly, retrofit to the right family, in this case turning her into Joseph’s own niece) and starts his own family. And he calls his first son Menashe because ‘Elokim made me forget all of my toil and ALL OF MY FATHER’S HOUSE’! At what point does Joseph decide to ‘return’ to the family? Unclear. I believe that it’s not until he can ‘no longer hold himself back’ – but my reason will wait for another time. Until then, he was planning on getting Binyamin away from them and sending them off. He was not figuring that the brothers would band together like they did, and he responded in kind.
It was at this point that Jacob, too, comes around and recognizes that his sojourn had never been complete (see his conversation with Pharaoh) and that his own destiny is in fact the destiny of a family and a nation, and not of an individual.