Why would he look to the ground?
Rashi: Perhaps he will find help from below. Hoshe'a ben Elah sent messengers to Soa Melech Mitzrayim (to help him against Melech Ashur).
Radak: He requests sustenance from residents of the land.
Malbim: Refer to 8:21:4:2.
Why does it say "v'Hine Tzarah [va'Chashechah]"?
Rashi: [Egypt] will not help them. Also Shevna went out to [make peace with] Sancheriv, and it was evil for him.
Radak: This is like "Tzukah va'Afelah"; The matter is repeated in different words.
Malbim: Affliction is on the land; darkness is in Shamayim above.
What is "Me'uf Tzukah"?
Rashi: It is tiredness [due to] affliction.
Radak: "Me'uf" is darkness, like "Eretz Eifasah Kemo Ofel" (Iyov 10:22).
Malbim: It is an internal affliction of the Nefesh. It is greater than the [external] affliction.
What is "Afelah Menudach"?
Rashi: Via darkness, he is Menudach (cast off). We find the expression Menudach with darkness - "Lachen Yihyeh Darkam Lahem ka'Chalaklakos ba'Afelah Yidachu v'Naflu Vah" (Yirmeyah 23:12). They are cat off to darkness.
Radak: This is like l'Afeilah. I.e. he sees himself cast off to darkness.
Malbim: It is darker than Chashechah. The verse depicts the Tzukah (Nefesh's affliction) and darkness as entities, and attributes to them fatigue and being cast off. After Tzarah destroys all residents of the land, there is no one to receive the Tzukah. It is weary from inability to do its action. Also the Ofel is cast off from place to take effect, for the darkness already destroyed the residents - "Ki Lo Mu'af [la'Asher] Mutzak" (23; the enemy did not tire).
