What is "Shenas ha'Deror"?
Rashi: It is the Yovel year. Radak ? this is like it says "u'Kerasem Deror ba'Aretz" (Vayikra 25:10)
What is the meaning of "v'Shavas"?
Rashi: This is like v'Shavah (it will return). Radak ? this is like "v'Shavah El Beis Aviha" (Vayikra 22:13). The Sov is in place of a Hei, like "Ki Azlas Yad" (Devarim 32:36) and similar verses.
What do we learn from "Ach Nachalaso Banav Lahem Tihyeh"?
Rashi: It is as if it says Ach l'Vanav Tihyeh Nachalaso ? it will not be given permanently to someone else (not a son).
Radak: It is as if it says Nachalaso Nachalas Banav Hu (his inheritance belongs to his sons); Lahem Tihyeh (it will be to them). Similarly, "Kis'acha Elokim" (Tehilim 45:7) is like Kis'acha Kisei Elokim.
Malbim: His inheritance is only for his sons. It will be veer to strangers. There is an argument about whether a gift is like a sale and returns in Yovel. The one who says that it does not return, a Nasi's law is different, like it explains the reason (refer to 46:18:1:1).
