Why is there a Patach under the Beis in "ba'Neshech"?
Radak: It is in place of the prefix Hei ha'Yedi'ah (to identify). It is the known Ribis, that the Torah forbade.
Why does it mention Neshech and Tarbis?
Radak citing Bava Metzi'a 60b: They are the same. The Torah used different expressions to put an extra Lav on one who transgresses.
Why does it say "Lo Yiten" and "Lo Yikach"?
Radak: "Lo Yiten" is at the time of the loan, when he gives 1 [the loan]; "Lo Yikach" is when he collects the loan.
Radak did not explain that "Lo Yiten" forbids paying Ribis. If it did, it should have said 'Neshech' or 'Im Neshech.' Rather, ba'Neshech is a loan on condition to return it with Ribis. (PF)
What is the meaning of "me'Avel Yashiv Yado"?
Radak: This is like the Torah forbade "Lo Sa'asu Avel ba'Mishpat ba'Midah ba'Mishkal uva'Meshurah" (Vayikra 19:35).
What is "Mishpat Emes"?
Radak: If one judges between two people, he does Mishpat, and does not favor one of them.
What is the reason for the Mitzvos listed in our verse?
Radak (6): After mentioning idolatry, which is Bein Adam la'Makom, it mentions Aveiros Bein Adam l'Chavero common in loans, and Mishpat Emes, which enables society to last.