Musar su Geremia 31:14

Rabbi Chiya continued his discourse, “On the day that the earthly Beis HaMikdosh was destroyed and Israel went into exile with a millstone around their necks and hands tied behind them, the Shechinah [Kenesses Yisroel] was also banished from the King’s palace to follow behind them. And as the Shechinah descended into exile it said, ‘First I will go and weep over My house and My children and the great unification that took place in the Beis HaMikdosh.’ “And when it descended from the Heavenly Beis HaMikdosh and saw the earthly Beis HaMikdosh in ruins with the blood of the righteous spilled therein and the sanctuary and portico burned down, it raised its voice in weeping, creating a stir in all the upper and lower worlds. Its voice ascended until it reached the abode of the King, evoking in Him the desire to destroy the world and return it primordial chaos, which prompted a number of camps of angels to descend to try to console the Shechinah, but I would accept no consolation. This is the meaning of the verse, ‘A voice is heard in Ramah, Rocheil weeping over her children, etc.’ “When the Shechinah left of the Temple it dwelt in the Land of Israel. Then it left the Holy Land to dwell in the desert, where it remained for three days, crying, ‘O how she sat in solitude, etc.’ (Eichah 1:1).”

The reason Rachel was buried on the wayside and not in the cave of Machpelah was to enable her to assist the Jews who were going into exile under Nebuzaradan. When they walked by her grave, the prophet (Jeremiah 31,14/15) describes her as weeping on behalf of her children, and G–d as promising her a reward for her efforts and assuring her that Israel would return to its land after a while.