What was the B'nos Tz'lofchad's claim?
Rashi, R. Bachye and Targum Yonasan: They were arguing that, since their father left no sons, either they should stand in place of sons [and inherit], or their mother should do Yibum with their father's brother 1 (and inherit both their father's portion and that of his deceased brother - Targum Yonasan). 2
Sifri: Based on a Gezeirah Shavah ?Shem? ?Yakum al-Shem Aviv? ? Devarim 26:6, in connection with Yibum ?, ?Shem? means ?Zera? (seed), meaning that, if they were not considered seed (to iherit), then their mothe should be allowed to make Yibum in order to establish seed for their deceased father.
What prmpted the B'nos Tz'lofchad to state their claim now?
Targum Yonasan and Sifri: Because they heard that only the males would inherit Eretz Yisrael (so they discussed among themselves what to do, 1 and came to the conclusion that, if people tend to favor males over females, Hashem has equal compassion on both, so they took their case to Moshe to place before Hashem - Sifri).
Bava Basra, 119b: Because Moshe happened to have been teaching the Dinim of Yibum, 2
Why did they add "ki Ein lo Ben"?
Rashi: This implies that had he had a son, they would not have claimed - to teach us that they were Chochmaniyos 1 (and that a son inherits his father - Bava Basra, 110b). 2
QUESTIONS ON RASHI
Rashi writes that either they should stand in place of sons, or their mother should do Yibum. What would they gain through Yibum?


