What is the meaning of "Ki Lo Mu'af la'Asher Mutzak Lah"?
Sanhedrin 94b: When Sancheriv came against Yerushalayim, Yeshayah told him that the nation (Yehudah) that wearies itself in Torah will not fall to its oppressor.
Rashi: Melech Ashur, to whom was given to afflict your land, he does not tire from coming against them, until three times - once in the days of Pekach "va'Yikach Es Iyon v'Es Avel? v'Es ha'Galilah Kol Eretz Naftoli" (Melachim II, 15:29). That was in Achaz' fourth year. In the 12th year, "va'Ya'ar Elokei Yisrael Es Ru'ach Pul Melech Ashur [? v'Es Pilnesser?] v'Yaglem la'Reuveni vela'Gadi vela'Chetzi Shevet Menasheh" (Divrei ha'Yamim I, 5:26). It was the beginning of Hoshe'a ben Elah's rebellion - "va'Yimtza Melech Ashur b'Hoshe'a Kesher" (Melachim II, 17:4), after being subservient to him for eight years. The calculation is not explicit in the verses, but we can learn from the Beraisa in Seder Olam. The third time was in Chizkiyah's sixth year, nine years after Hoshe'a's rebellion; Shomron the capitol was captured, and all of them were exiled.
Radak: Yisrael did not consider itself in darkness that comes to the land initially. I.e. it still did not feel its affliction when Zevulun and Naftoli were exiled. Mu'af is an expression of darkness, like "Eretz Eifasah Kemo Ofel" (Iyov 10:22). "Lah" refers to the land.
Malbim: Melech Ashur, the afflicter, will not tire from coming time after time to destroy the land.
What is the meaning of "ka'Es ha'Rishon Hekal Artzah Zevulun [v'Artzah Naftoli]"?
Rashi: This middle exile will be light, like the first one, in which only Zevulun and Naftoli were exiled. Also in the second, only the two and a half tribes in Ever ha'Yarden were exiled.
Radak: The first to exile, Tiglas Pil'eser, who exiled [Gad 1 ], Reuven, Chetzi Menasheh, Zevulun and Naftoli (refer to 8:23:1:2), was light (mild); refer to 8:23:3:3.
Radak citing Sanhedrin 94b: The fate of the first ones (the 10 Shevatim) who lightened (cast off) the yoke of Torah is not like the latter ones (Yehudah), who accepted a heavy yoke of Torah. They are worthy of miracles like those who passed through Yam Suf and walked across the (dried up) Yarden (when Bnei Yisrael entered Eretz Yisrael).
I do not know why Gad is omitted from all texts of Radak. (PF)
Why does it say "veha'Acharon Hichbid"?
Rashi #1: The last exile swept away everything, like one who is Mechaved (sweeps) the house.
Rashi #2: "Hichbid" is an expression of Kaved (heaviness); the verse called the first exiles Kal (light). Malbim - they were light, for they were not Kelalis (of the entire nation). The last was Kelalis.
Radak: The latter to exile, Sancheriv 1 , was harsh. He exiled the rest of the tribes.
Refer to 8:23:2:3.
This is unlike Sanhedrin 94a, which says that Tilgas Pilne'eser (the first to exile) is another name of Sancheriv. (PF)
Why does it say "Derech ha'Yam"?
Rashi: This refers to those who dwell by the sea of Tiverya, i.e. Eretz Naftoli - "Yam v'Darom Yerashah" (Devarim 33:23).
Radak: Because Sancheriv did not exile Yerushalayim, which is in the middle of Eretz Yisrael, it mentions the place on the borders of Eretz Yisrael - the sea and the Yarden. He did not conquer Yehudah until the days of Chizkiyah, and it was only temporary - once his camp was struck when he came against Yerushalayim, Yehudah returned.
What does "Ever ha'Yarden" refer to?
Rashi: It is the second exile, of Reuven and Gad [Malbim - and Chetzi Menasheh, who were in Ever ha'Yarden].
Radak: Refer to 8:23:4:2.
What is "Galil ha'Goyim"?
Rashi: It is all of Eretz Yisrael, which was Goleles ('rolled') to it all Goyim; all desired it and came there for business - "Nachalas Tzvi Tziv'os Goyim" (Yirmeyah 3:19).
Targum Yonasan: Great cities of Goyim.
Radak citing Sanhedrin 94b: Hashem said, if Sancheriv will renounce his intention to attack Yerushalayim, fine. If not, I will make him Galil of the nations. (Rashi 94b -Yegalgel (he will roll) in shame among all nations. Or, Galil is an expression of Galal (excrement).)
Malbim: The Gelilos (regions) of all the tribes [were subject to the last exile].