Albert Barnes Commentary Isaiah 37:33

"Therefore thus saith Jehovah concerning the king of Assyria, He shall not come unto this city, nor shoot an arrow there, neither shall he come before it with shield, nor cast up a mound against it." — Isaiah 37:33 (ASV)

He shall not come into this city - Sennacherib probably encamped on the northeast side of the city, and his army was destroyed there (see the notes at Isaiah 10:28 and following).

Nor shoot an arrow there - That is, nor shoot an arrow within the walls of the city.

Nor come before it with shields - (See the note at Isaiah 21:5). The meaning here is that the army would not be permitted to come before the city defended with shields and prepared with the means of attack and defense.

Nor cast a bank against it - A mound; a pile of earth thrown up in the manner of a fort to defend the assailants, or to give them an advantage in attacking the walls. Sieges were conducted by throwing up banks or fortifications, behind which the attacking army could be secure to carry on their operations. Towers filled with armed men were also constructed, covered with hides and other impenetrable materials, which could be made to approach the walls, and from which those who were within could safely conduct the attack.