Why did he say "Ulai"? What is the Safek?
Malbim (Yeshayah 37:4): Perhaps Ravshake is merely his master's Shali'ach to revile. If so, Sancheriv should be punished.
What is "Lecharef Elokim Chai"?
Radak: He reviled Hashem, and said that He cannot save Yerushalayim.
Radak citing Targum Yonasan: He shamed the nation of the living G-d.
What is "v'Hochi'ach"?
Rashi: Ravshake 'proved' (justified his words) via Sancheriv's successes.
Radak, Targum Yonasan: Hashem will rebuke (punish) for the words that He heard.
Malbim (Yeshayah 37:4): He 'proves' his blasphemy with claims - "where are the gods of Chamas
What is the meaning of "v'Nasasa Sefilah Be'ad ha'She'eris ha'Nimtza'ah"?
Malbim (Yeshayah 37:4): The merit of Tefilah should help to save the remaining tribes that were not exiled yet.
