What are the implications of "la'Nochri Sashich"?
Rashi (citing Bava Metzi'a 70b): It comes to instigate a La'av that stems from an Asei 1 - you may charge Ribis to a Nochri, but not to your brother! 2
Ramban: It implies that one may take Ribis from a Nochri. 3
Seforno: It teaches us that, having agreed to give the Nochri Ribis, one should keep one's word.
Rambam (Hilchos Malveh 5:1): It is a Mitzvah to take Ribis from a Nochri. 4
Bearing in mind that stealing from a Nochri is prohibited (See Bava Kama, 113b), why is taking Ribis from him permitted?
Ramban: Because, unlike stealing, Ribis is given with the consent of both parties, and the Torah only forbids it because lending to one's Jewish brother is a Chesed, 1 which is not the case by a Nochri. 2
Ramban: Based on the Pasuk in Vayikra 19:18 "Ve'ahavta le'Re'acha Kamocha," and as the Pasuk indicates in 15:9. Refer also to 23:20:1:1.
Ramban: And it is for the same reason that one is permitted to claim one's debt from a Nochri after the Shemitah - See 15:3.
Why does the Torah repeat "u'le'Achicha Lo Sashich!"?
Seforno: To forbid giving him Ribis even if one made an agreement to do so. 1
What is the significance of the words "be'Chol Mishlach Yadcha al ha'Aretz ... "?
Oznayim la'Torah: Because the Torah mentioned "Neshech Kesef" and "Neshech Ochel", and one normally borrows money to enter into a business venture and food when one's harvest failed. Therefore Hashem rewards the creditor 'Midah ke'Neged Midah'.
Why does the Torah bestow a Berachah upon someone who lends without Ribis?
Ramban: Because lending without Ribis is an act of Chesed, 1 which results in a Divine blessing.
Seforno: The Berachah refers to the first issue in the Pasuk - a person who keeps his word and pays his Nochri creditor the Ribis that he agreed upon, and the Berachah comes for avoiding creating a Chilul Hashem.
