What is the significance of returning the exile?
Malbim: This is returning their level.
What do we learn from "v'Shasu Es Yeinam... v'Achlu Es Perihem"?
Radak: They will not toil for naught, that they will work their land and their neighboring enemies will consume, like happened when they were on their land before its destruction. That was when they did not do Hashem's will. Also Yeshayah said "u'Vanu Vatim v'Yashavu v'Nat'u Keramim v'Achlu Piryam" (65:21). There it says that they will eat from their vineyard, and here it says that they will drink. These are the same - grapes are for eating and drinking the wine that comes from them. The same applies to other crops and trees (they will consume them).
