Our parasha begins with an eerily familiar scenario. Yaakov, an old, blind patriarch, embarked upon the task of blessing two brothers of his offspring. The decision had to be made as to who would receive the coveted blessing and who would not. This is just the position that Yitzchak had been in a generation before.
However, there is a big difference in the outcome. Yaakov ended up getting the beracha, whereas Eisav was rejected. In contrast, Ephrayim received the more prominent beracha and status, but Menashe was not rejected and also received a very respectable blessing. He is one of the ne’arim who was blessed with the angel looking after him (Bereishit 48:16), and fathers have henceforth blessed their sons to be "like Ephrayim and Menashe" (ibid. 20). Menashe’s partial prominence finds expression with Yaakov switching his right hand to Ephrayim’s head, while still keeping Menashe opposite his right side, "for Menashe is the firstborn" (ibid. 14). We will try to appreciate this dichotomy with the help of Rav Mordechai Breuer, one of the trailblazers of a new-old approach to learning Tanach.
Reuven is the first firstborn to lose his hold on that status, as Yosef becomes the "crown of his brothers" (ibid. 49:26) yet still remain in a prominent place within the family hierarchy. Menashe "follows his uncle’s lead." Reuven received a portion on the eastern bank of the Jordan, a much less spiritually choice part of Eretz Yisrael, and was joined there by Gad, the firstborn of Zilpah, the maidservant of his mother, Leah. Menashe’s land actually comes in two parts, one in the main, western part of Eretz Yisrael and the other in the eastern side. This seems to fit his "split legacy." But why?
Menashe had two wives, one who was Jewish and one who was Aramaic, as it says in Divrei Hayamim (I:7:14). The Aramaic wife (whom he married before the Torah was given, obviously) was a princess whom he married to strengthen his royal status in Egypt (see Yerushalmi, Sanhedrin 2:3). This decision was divinely repaid mida k’neged mida – instead of this raising his status, it lowered it. His descendants from his Jewish wife received their portion in the Land on the western side. His descendants from the Aramaic wife (Machir, father of Gilad) had to settle for the eastern portion, along with Reuven and Gad.
Menashe’s key to familial survival is Yaakov’s statement, "Ephrayim and Menashe are to me like Reuven and Shimon." If they are like sons, then Menashe is not a firstborn and does not have the stigma of being cast off from that status. Yosef is like a firstborn and receives a double portion (two tribes). Ephrayim, who is not a firstborn, receives a very large portion in the heartland of Eretz Yisrael. Menashe, as a firstborn of Yosef, gets a double portion of sorts, but those of his descendants who are tainted with intermarriage receive an inferior land. This explains the two different treatments that different parts of Menashe’s tribe experienced.
As we fight the ravages of intermarriage in our times, the message of the importance of this struggle should be reinforced by the lessons from its ancient roots.