Parashas Behar · Aliyah 5 · Passuk 25:32
Chabad.org — English translation + Rashi
Torah Temimah cites Sifra / Arakhin 33b.
English: “An everlasting right of redemption shall be for the Leviim.” This teaches that the Leviim may redeem forever.
Classical derasha (Sifra / Bavli Arakhin).
Houses in the cities of the Leviim may be redeemed at any time, without the one-year limit that applies to ordinary walled cities.