Rashi: In the hand of the harshest of Goyim, Nebuchadnetzar. In his first year, he conquered Ninveh ¹ (Megilah 11b). Radak ? this is like Seder Olam. In easterners' texts, there is a Yud in Eil; it is like "v'Es Eilei ha'Aretz Lakach" (13:13) ? the strong ones. The same applies to westerners' texts, which do not have a Yud.

Malbim: In the hand of Nebuchadnetzar, the strongest Goy, and the Goyim consider him to be a god. Also Nebuchadnetzar is compared to a great cedar ? "Hashem Tzevakos Mesa'ef Purah b'Ma'aratzah; ? veha'Levanon b'Adir Yipol" (Yeshayah 10:33-34). Hashem Himself cut him off, and via an Adir (angel). Then, he was not yet expelled, and his kingship endured. Now that I expelled him, I did not hand him over to angels, rather, to Goyim.

Rashi: Nebuchadnetzar will do to [Ashur] as he desires.

Malbim: I handed over [Melech Ashur] to a Rasha like himself.

Radak: It applies to what came before ("Aso Ya'aseh Lo") and what is after ("Gerashtihu").