1)
What is the meaning of "Hidichu"?
1.
Radak, Malbim: They cast off. This is a metaphor for the kings of the nations, who exiled Yisrael from their land.
2)
Why does it say "ha'Rishon Achalo"?
1.
Rashi: He exiled the 10 tribes.
2.
Radak, Malbim: He ate the meat, and left only the bones (Yehudah and Binyamin). Malbim - he (Melech Ashur) is the lion.
3)
What is the meaning of "Itzmo"?
1.
Rashi: He crushed the bones [Radak - until nothing remained. He exiled Yehudah and Binyamin, and destroyed Yerushalayim and all Arei Yehudah.