What is the meaning of "Keshes Giborim Chatim"?
Rashi: Hashem's practice is to weaken the strong.
Mahari Kara, Metzudas David: The bows of the strong, they break.
Bi'ur ha'Gra: The strength of Sichon and Og was broken in the days of Moshe.
If Chatim applies to Keshes, it should say Chatah (singular)!
Radak: It refers to Giborim. They and their bows [He weakens]. We find like this - "Haysah Elav Pnei ha'Milchamah" (Shmuel 2 10:9), "Kol Negidim Nechba'u" (Iyov 29:10). 1
Malbim: Keshes 2 refers to all bows. This is like "Etz Pri", "va'Yhi Li Shor va'Chamor" (Bereishis 1:11, 32:6). 3
I.e. Haysah refers to ha'Milchamah, and not to Pnei, and Nechba'u refers to Negidim, and not to Kol.
Radak (Shmuel II, 22:35): Keshes can be masculine or feminine - "v'Nichas Keshes" (22:35), "v'Nichasah Keshes" (Tehilim 18:35).
What is the meaning of "Azru Chayil"?
Radak: Valiance and strength is their belt with which they gird.
Bi'ur ha'Gra: This refers to the war against Midyan. The Nichshalim (Yisrael stumbled with Benos Midyan and Ba'al Pe'or) were valiant (12,000 of them wiped out Midyan).
