Which towns is the Pasuk referring to
Rashi: It is referring to the forty-eight towns that were given to the Levi'im. 1
See Mas'ei, 35:1-8.
What are the implications of "Ge'ulas Olam?
Rashi: It implies that, if a Levi sells a field that is given to him within the two thousand Amos surrounding the town, he may redeem it immediately, even before two years; And if he sells his house in the walled town, he may redeem it even after one year.