All of Israel are friends
In the first verse of Parshat Beshalach, Shmot 13:17 we read:
When Pharaoh sent away the people, God did not lead them by the way of the land of the Plishtim although it was the shortest route; for God said, “The people might change their minds should they encounter war, and return to Egypt.”
Why did God make the trip to the Land of Israel longer?
In the Midrash, Shmot Rabba 20:14, Rabbi Yehoshua ben Levi answers:
It can be compared to a king who had twelve sons and ten estates. The king thought to himself: “If I give the ten estates to my sons, I will create strife between them: I had better wait until I purchase another two estates and then divide them equally between all of my sons.”
God said: “If I bring them now into the Land, there will not be enough portions for all twelve tribes; I better delay them in the wilderness until they have inherited the other side of the Jordan, and until the tribes of Reuven, Gad and half of the tribe of Menashe have taken their portions, and then I will bring B’nai Yisrael into the Land.”
Therefore it says: “God did not lead them by the way of the land of the Plishtim” since if they had gone that way, they would not have conquered the land of Sichon and Og, on the other side of the Jordan.
Every tribe was promised their own portion of land, described in Yaakov’s blessings to his sons in Parshat Vayechi and in Moshe’s blessings to the tribes in Parshat Vezot HaBracha.
In the future, all of the tribes will once again return to their ancestral territory in the Land of Israel.
The Rambam explains in Hilchot Melachim 12:3:
During the era of the Messianic king, once his kingdom has been established and all of Israel has gathered around him, the entire nation’s line of descent will be established on the basis of his words and the prophetic spirit which will rest upon him…He will purify the lineage of the Levites first, stating “He is a Kohen of defined lineage. He is a Levi of defined lineage.” Those whose lineage he will not recognize will be lowered to the status of Israelites…When he defines the lineage of the Israelites, he will make known their tribal lineage alone, stating: “He is from this tribe and he is from another tribe.”
The tribes will go up to Jerusalem on Pesach, Shavuot and Sukkot. There they will all be friends with each other and will become one complete nation.
May the return of all of the Jewish people to Israel come swiftly in our days. In the mean time, let’s continue to work on unifying the Jewish people.