What is "va'Ygal"?
Rashi: It is an expression of Giluy (exposure).
What is "Masach Yehudah"?
Rashi: It is the Beis ha'Mikdash, which protects and covers over them.
Radak: They thought that the Beis ha'Mikdash protects over them, and no evil can come to them, because the Mikdash is in their inheritance. The enemy came due to their sin, and revealed their covering.
Malbim: It is the wall that covers over them.
What will they look at?
Rashi: Strategies to fight them.
Radak: He addresses Yerushalayim or the king. When you saw that the enemy came against you, you looked at the weapons of Beis Ya'ar ha'Levanon, where Shlomo put shields. You thought to bring them to Yerushalayim. You prepared yourself for war, and not for Teshuvah and good deeds. I.e. you put your trust in weapons, and not in Hashem - "v'Lo Hibatetem El Oseha" (11).
Malbim: Only then they will look at the weapons that earlier kings left in Beis Ya'ar ha'Levanon, which is the arsenal of Malchei Yehudah. You should have done so immediately, before the wall was breached!
What is the meaning of "El Neshek Beis ha'Ya'ar"?
Rashi: They are the 320 shields that Shlomo made; "va'Yitnem ha'Melech Beis Ya'ar ha'Levanon" (Melachim I, 10:17).
Radak citing Targum Yonasan: To the weapon of the hidden storehouse of the Mikdash.
