What is the meaning of "Yipol"?
Rashi: Will camp. This is like "Al Pnei Kol Echav Nafal" (Bereishis 25:18).
Radak #1: They will fall (die) in war (Malbim #1 - via arrows).
Radak #2, Malbim #2: They will die from a plague.
What is "mi'Tzidcha"?
Rashi: It is your left 1 .
Yuma 53b: This shows that after Shemoneh Esre, one bows first to his left, and then to his right. Tosfos - the verse teaches that we request about the left (which is Hashem's right) first.
Who are to his right and left?
Rashi: They are demons (Brachos 6a - Mazikim); they will not approach you to damage you.
Radak: They are people fighting each other, and you need to pass between them.
