Isaiah 37:8
So Rabshakeh returned, and found the king of Assyria warring against Libnah: for he had heard that he was departed from Lachish. So Rabshakeh returned, and found the king of Assyria warring against Libnah: for he had heard that he was departed from Lachish.
The chapter is the parallel to 2 Kings 19, linking the two accounts together, though its wording differs considerably from that chapter. The verse belongs to the record of Sennacherib's campaign against Judah, which came from the southwest, in contrast to the campaign described in Isaiah 10, which came from the northeast and was Sargon's. At this time Sennacherib was warring before Lachish, about thirty-four miles southwest of Jerusalem, when he sent his servants to Hezekiah and to Judah at Jerusalem. He had overcome Babylon and then moved his armies westward, with Sidon surrendering, Syria submitting, the Egyptian allies defeated, and Ekron taken, then turning upon Judah had taken forty-six cities and was approaching Jerusalem. Hezekiah in alarm had sent a large tribute to Sennacherib at Lachish, but it did not pacify the invaders, who took it as a confession of weakness.
Rabshakeh returned to the king of Assyria and found him warring against Libnah, having heard that he had departed from Lachish, placing the king and his army at Libnah after leaving Lachish. The verse stands within the history of Hezekiah's reign when the king of Assyria came up and threatened Hezekiah and Jerusalem and the land. It stands within the sequence of Hezekiah's humility, God's message to him through the prophet, and the Lord's wonderful deliverance of Judah from Assyrian power by His angel. The Assyrian threat does not prevent God from delivering His people.
When Hezekiah was taunted by his enemies and faced the invading army, he spread the insulting letter before the Lord, God delivered him, and the invading army lost 185,000 men in one night. The Assyrian army was with its king at Libnah when the angel struck down the 185,000 men, rather than near Jerusalem. This rules out that destruction as the fulfillment of Isaiah 30:33.
The destruction recorded in Isaiah 37 is God's most notable witness to Assyria that He is God above all, in the slaughter of Sennacherib's host. After Assyria rose to world power and influence following Egypt and had grown corrupt and gone far from God, God bore witness to it again and again by revelation and living testimony. He first sent the Hebrew prophet Jonah to call it to repentance, with this destruction as the chief example by which He left Himself not without witness. The account shows that God is with those who stand alone against wrong and can deliver them when human support fails.