Before Yosef reveals himself to his brothers, as told in Parashat Vayigash, he weeps, as he had done several times earlier throughout this story. Here, he cries so loud "that the Egyptians could hear" (45:2). Perhaps it is the Torah's emphasis on the volume of this sob that led Chazal to afford it symbolic significance. The Midrash (Bereishit Rabba 93:13) comments, "Just as Yosef appeased his brothers only with weeping, so will the Almighty redeem Israel only with weeping, as it says, 'They shall come with weeping, and with compassion will I guide them' (Yirmiyahu 31:9)."
How exactly does this Midrash understand the importance of "weeping" in this narrative, and how does this relate to that prophecy in Sefer Yirmiyahu?
One approach to explaining this Midrash might be to understand the context of Yirmiyahu's prophecy referred to in this passage. As we discussed in our S.A.L.T. series to Rosh Hashanah this past year, this prophecy (which we read as our haftara for the second day of Rosh Hashanah) appears to foresee specifically the return of the Northern Kingdom of Israel, or the Ten Lost Tribes. (Rav Mendel Hirsch, in his work on the haftarot, emphasizes this point.) Throughout this prophecy, Yirmiyahu refers to Am Yisrael as "Efrayim," which clearly refers to the Northern Kingdom. Efrayim was the largest and most influential tribe in the Kingdom, and in fact, the Kingdom was founded by Yeravam Ben Nevat, who was from the tribe of Efrayim. Yirmiyahu predicts that "again you shall plant vineyards on the hills of Shomron" (31:5). The city Shomron was capital-city of the Northern Kingdom, and the region of Efrayim in general is often referred to as Shomron (as it is today; "Samaria," or "Shomron," is the northern section of the West Bank). Similarly, Yirmiyahu declares, "For the day is coming when watchmen shall proclaim on the heights of Efrayim: Come let us go up to Zion, to the Lord our God!" (31:6). The Ten Tribes of the North had dissociated themselves entirely from Jerusalem and the Temple, and, according to Chazal, blockades were erected to prevent pilgrimages from the northern tribes to Jerusalem. But Yirmiyahu foresees the day when pilgrims from the North will once again bring their fruits to Jerusalem as required by the Torah, when the Ten Tribes will become part of a unified Am Yisrael, with one kingdom, one country, and one Temple uniting the entire nation.
With this in mind, we can perhaps gain a clearer understanding of the association Chazal draw between Yosef's emotion as he reveals himself to his brothers, and that foreseen by Yirmiyahu. Both Parashat Vayigash and this prophecy of Yirmiyahu tell of the reunion between Yosef (or the tribe of Efrayim, the larger of the two tribes that emerged from Yosef) and his brothers after years – or, in Yirmyahu's case, centuries – of estrangement. With tears and emotion, the Northern Kingdom of Israel will return to the Jewish people; it will, like Yosef, reveal its true identity that had been concealed for so many years under the disguise of foreign nationality and loyalty. In the spirit of "ma'aseh avot siman la-banim" (that which happened to the patriarchs foreshadow what will happen to their descendants), Chazal saw within Yosef's revelation to his brothers the symbol of the ultimate reunion between the Northern Kingdom and the Kingdom of Yehuda, with the arrival of the final redemption.