What is "ha'Tzefoni"?
Rashi #1: It is the army of locusts. "V'Hidachtiv El Eretz Tziyah u'Shmamah" applies to it. Radak - they are called ha'Tzefoni, for they came from Tzafon (the north).
Targum Yonasan: It is the nation that comes from the north. Rashi #2 - this is Melech Ashur.
Rashi citing Sukah 52a: It is the Yetzer ha'Ra, which is Tzafun (hidden) in man's heart. Radak - in the days of Mashi'ach, Hashem will distance it. Malbim - the snake does not kill. Sin kills! The Yetzer ha'Ra is the reason why the locusts came. Via distancing it, the result of sin (locusts) will be distanced.
Why will He send it to "Eretz Tziyah u'Shmamah"?
Radak: It will not find food there, so it will die - therefore, "v'Alah Vasho."
Radak (based on Sukah 52a): There are no people there [for the Yetzer ha'Ra] to confront them.
Malbim: (a) He will send it far away. If the salvation was only for His name, He would leave it close, to be ready if they will sin again! (b) If the salvation was only for His name, He would send it to take vengeance against other nations who disgraced His name 1 , and for Yisrael to be chastised - "Hichrati Goyim...; Amarti Ach Tir'i Osi Tikchi Musar" (Tzefanyah 3:6-7). However, now that He did so for Yisrael, He will send it to a Midbar.
Why must we say so? Hashem exacts payment from man only after his measure for sin is full (Sotah 9a), i.e. from one whom He hates (Avodah Zarah 4a)! (PF)
What is the meaning of "[u'Shmamah Es Panav El] ha'Yam ha'Kadmoni v'Sofo El ha'Yam ha'Acharon"?
Rashi: The eastern sea. Radak - this is Yam Kineres, or Yam ha'Melach. They are in the east of Eretz Yisrael. Ha'Yam ha'Acharon is Yam ha'Gadol (the Mediterranean), to the west of Eretz Yisrael. Panav is the head [of the army of locusts]. It was so great that it spanned from the eastern sea to the western sea.
Rashi citing Sukah 52a: Ha'Tzefoni is the Yetzer ha'Ra; Hashem will distance it, for] it set its face against Bayis Rishon and Bayis Sheni, and destroyed them [Radak - and Chachamim in Bayis Sheni].
Rashi: According to Targum Yonasan, that ha'Tzefoni is Melech Ashur, I will send some of his army to the east, and some to the west.
Malbim: The verse depicts that the locusts stretched across all of Eretz Yisrael, from sea to see. When the decree ceased, they were divided into two; the eastern half (Panav) went to the eastern sea, and the western half (Sofo) went to the western sea.
Why does it say "Basho" and "Tzachanaso"?
Rashi: "Vasho" (stench) reveals that Tzachanaso is an expression of filth.
Radak: Tzachanaso is Vasho; the matter is repeated in different words. It says "Alah", for the odor will rise to the nose of those who pass.
Malbim: When locusts depart, they leave a foul odor - Tzachanaso from its seed, and Vasho from the many that will die - "va'Tiv'ash ha'Aretz 1 " (Shemos 8:10).
That verse discusses the stench from the dead Tzefarde'im; Malbim explains that also dead locusts stink. (PF)
In what way "Higdil La'asos"?
Rashi: It stretched its hand against great ones.
Radak: The locusts did great evil in Eretz Yisrael, and Hashem had mercy on the land and killed it.
Radak (based on Sukah 52a): The Yetzer ha'Ra ignores other nations and confronts Yisrael, and Chachamim more than everyone.
Malbim: There are prone to be plague and illness due to mold in the air after the locusts die. The verse promises that the stench will depart, for Higdil La'asos - they already did their full mission and a great destruction, and caused Teshuvah. There is no need to increase afflictions via them.
