Parashas Behar · Aliyah 1 · Passuk 25:13
Chabad.org — English translation + Rashi
Torah Temimah cites Sifra (Torat Kohanim).
English: “You shall return.” To include one who sells his field and his son stands up and redeems it — that it returns to his father at Yovel.
Classical derasha (Sifra).
If a son redeems the field that his father sold, the field still reverts to the father (the original owner) at Yovel.