What do we learn from "ha'Nas mi'Kol ha'Pachad Yipol El ha'Pachas"?
Rashi: One who escapes the sword of Mashi'ach ben Yosef, he will fall to the sword of Mashi'ach ben David. And one escapes [Mashi'ach ben David's sword] will be caught in the pit of the war of Gog.
Why does it say "Ki Arubos mi'Marom Niftachu"?
Radak: Because decrees descend from Shamayim, the verse depicts as if rain overpowers, like it says in the Mabul "va'Arubos ha'Shamayim Niftachu" (Bereishis 7:11). So a multitude of decrees will descend from Shamayim, like the Mabul. Refer to 24:18:3:1.
Malbim: The verse depicts the horror that will come to the land time after time. The land will shake from its place and its pillars will tremble. Sometimes the land shakes due to supreme signs. Here it says that it will not be due to such signs. The windows of Shamayim will be opened to bring down new evil decrees of Hashem.
Why does it say "va'Yir'ashu Mosedei Aretz"?
Radak: The residents will not have any standing [due to all the punishments].
Malbim: Refer to 24:18:2:2.