To what were Rivkah's mother and brother referring when they blessed her 'Our sister. May you number thousands upon tens of thousands!"
Rashi: They were referring to Hashem's Berachah to Avraham following the Akeidah - expressing their hope that that Berachah should be fulfilled on her children 1 and not on the children of any other woman. 2
Why did they say 'Our sister'?
Targum Yonasan: 'Until now', they said to her, 'you were our sister; now you are about to marry a Tzadik... '.
What resulted from Rivkah's Brachah from Lavan and her mother?
Hadar Zekenim (citing a Midrash 1 ): It caused her to be barren until Yitzchak prayed for her, lest they say that their Brachah helped.
Perhaps he refers to Yalkut Shimoni,109 (PF).
What is "v'Yirash Zar'ech Es Sha'ar Son'av"?
Ha'Emek Davar: This is a Brachah of quality; your seed should be Chachamim who sit in the gate, even in the gate of those who hate them, because they need their wisdom and counsel. 1
We find that Achashverosh hated the Jews (Megilah 14a), yet Mordechai sat in the king's gate, and the king first asked Chachmei Yisrael what to do to Vashti (Megilah 12b)! King Ferdinand forced every Jew to give up his faith or leave Spain, but he wanted the Abarvenel to be his finance minister! (PF)
Avraham was blessed "v'Yirash Zar'acha Es Sha'ar Oyvav" (22:17). Why did they say "Sha'ar Son'av"?
Ha'Emek Davar: Son'av implies that they do evil acts; they are known. Oyvav is even those who hate in the heart, and do not act upon it. People are unaware of this wonder, that even the Jews' enemies will need their Chachmah; they see only that Son'ei Yisrael need Chachmas Yisrael.