John Gill

And I will camp against thee round about,.... Or as a "ball" or "globe" (o); a camp all around; the Lord is said to do that which the enemy should do, because it was by his will, and according to his order, and which he would succeed and prosper, and therefore the prophecy of it is the more terrible; and it might be concluded that it would certainly be fulfilled, as it was; see Luk 19:43, and will lay siege against thee with a mount: raised up for soldiers to get up upon, and cast their arrows into the city from, and scale the walls; Kimchi and Ben Melech interpret it a wooden tower. This cannot be understood of Sennacherib's siege, for he was not suffered to raise a bank against the city, nor shoot an arrow into it, Isa 37:33 but well agrees with the siege of Jerusalem by the Romans, as related by Josephus (p): and I will raise forts against thee; from whence to batter the city; the Romans had their battering rams. (o) "quasi pila", Piscator; "instar globi", Gataker. (p) Joseph. de Bello Jud. l. 5. c. 7. sect. 1. & c. 12. sect. 1, 2.