2 Chronicles 32:19
And they spake against the God of Jerusalem, as against the gods of the people of the earth, which were the work of the hands of man. And they spake against the God of Jerusalem, as against the gods of the people of the earth, which were the work of the hands of man.
The Assyrians, through Sennacherib's men, messengers and representatives, spoke against the God of Jerusalem as if He were like the gods of the peoples of the earth. Those gods were powerless idols, the work of human hands, mere human artifacts, wholly unlike the living God. To treat Jerusalem's God as one of them was blasphemy against the true and living God, ignoring the difference between Him and handmade gods. Their taunt denied His power to deliver Jerusalem, and was meant to belittle Him and discourage the city. The attack was against God Himself, not merely against His people.
God answered that contempt by delivering Jerusalem and overthrowing the Assyrians by His angel. The deliverance came in response to humiliation and prayers when the Assyrians pressed the battle to the city in Hezekiah's reign. He struck the leaders and captains of the Assyrian army, and Sennacherib returned home in shame. The miraculous defeat showed that the living God is greater than human strength and false gods.
Read with 2 Kings 18-19 and Isaiah 37, the accounts of the Assyrian campaign show that the army was not near Jerusalem when the angel struck down 185,000 men, but was with the king of Assyria at Libnah. That destruction is therefore not the fulfillment of Isaiah 30:33. The verse belongs to the account of Sennacherib's wars against Judah, his siege of Jerusalem, and his defeat, after which he died at the hands of his sons while worshiping the idol he had trusted.
The messengers from Babylon likewise regarded the God of Jerusalem as no different from the nations' man-made gods. Hezekiah had the opportunity to show them that Jerusalem's God alone had saving power, but he displayed his own wealth instead of bearing witness to God. The account teaches that God's people need not use carnal weapons to defend themselves even when facing an armed foe, for their struggle is not against flesh and blood unless they choose to make it so.