What is Hashem's Kin'ah for His land?
Rashi: This is like "ha'Mekanei Atah Li" (Bamidbar 11:29). Her affliction entered His heart, and He fought her war and engaged in her needs.
Rashi citing Sotah 3a: It is an expression of warning. He warned the locusts about matters of His land.
Radak: This is a Nevu'ah that after they will repent, Hashem will accept their prayers, and have Kin'ah for His land that it not be desolate. The reason for the Kin'ah is because it was a disgrace among the Goyim. "L'Artzo" means for the sake of Artzo. The same applies to "ha'Mekanei Atah Li" (Bamidbar 11:29).
Malbim: This corresponds to "v'Al Titen Nachalasecha l'Cherpah" (17).
What is the significance of having mercy on His nation?
Malbim: This corresponds to "Chusah Hashem Al Amecha" (17). Midrash Rus (2:11) asks, it says "Ki Lo Yitosh Hashem Amo v'Nachalaso Lo Ya'azov" (Tehilim 94:14), and it says "Ki Lo Yitosh Hashem Es Amo Ba'avur Shmo ha'Gadol" (Shmuel I, 12:22)! When Yisrael do His will, He does for His nation and Nachalah. When Yisrael do not do His will, He does for His great name. The Kohanim prayed that He do for His great name, even though Yisrael were not worthy - "Lamah Yomeru va'Amim Aye Elokeihem" (17). It says "Chusah Hashem Al Amecha", for Chas is compassion for something needed. One does not destroy it, for he benefits from it - in this case, honor of His name which is joined to them. After Yisrael repent, He will do for the sake of His nation. Chemlah is mercy due to perfection of the matter itself, not because he needs it. Yisrael will be Tzadikim, and Shelemim. There are seven differences between doing for His great name, and for His nation. (a) If it is for His name, He would answer the Kohanim - they prayed for this! However, the salvation was for His Am and Nachalah, in Yisrael's merit - therefore, "va'Ya'an Hashem va'Yomer l'Amo" (19). Also refer to 2:19:3:1-2, 2:19:4:2, 2:19:5:1, 2:20:2:3.
