Why does the Torah write 'Achei Yosef" rather than 'B'nei Ya'akov'?
Rashi: To teach us that, remorseful of having sold Yosef, they decided to reinstate their brotherhood and to redeem him for as much as was asked of them.
Malbim: Shamayim caused this in order to fulfill the first dream. 1
Why does it add the word "Asarah"? Why was it not obvious that they were ten, seeing as Binyamin did not accompany them (as the next Pasuk tells us)?
Rashi: To teach us that although their attitudes towards Yosef differed, as far as purchasing grain was concerned, they were of one heart.
Seforno: Because the seller would only sell grain per household, not to individuals and not in bulk (for whole communities). 1
Oznayim la'Torah #1: To teach us that the suffering that they encountered on their trip as a punishment for selling Yosef was due to all of them 2
To prevent it from being sold on the black market, as is customary in times of famine (Seforno).
Oznayim la'Torah: And Hashem prevented Binyamin from going with them because he had done nothing for which he deserved to suffer. Even though he went down the second time and suffered, the Simchah over being reunited with Yosef more than compensated for this.
