What is the meaning of "ba'Ir Yashoku"?
Rashi: This refers to making noise, like "k'Mashak Gevim" (Yeshayah 33:4), "v'Dov Shokek" (Mishlei 28:15), "mi'Meshak Charul" (Tzefanyah 2:9). Malbim - when they are in the city, they make noise in the streets.
Rashi citing Targum Yonasan: "Yashoku" is an expression of weapons - they are armed.
Radak: "Yashoku" is an expression of Shok (the thigh). It is said regarding locusts, for its thighs are long. Also, it constantly goes, and rests only a little. Also "k'Mashak Gevim Shokek Bo" (Yeshayah 33:4) and "u'Ven Meshek Beisi" (Bereishis 15:2) hint to constant motion.
What do we learn from "Be'ad ha'Chalonim"?
Radak: This is like Min ha'Chalonim. The same applies to "Be'ad ha'Sevachah" (Melachim II, 1:2), "Be'ad ha'Chalon" (Shoftim 5:28). They are unlike other enemies, that one closes the gate in front of them. They enter the house like a thief who finds the gate closed, and strives to enter via the windows.
