From a blogpost I shared nearly a year and a half ago…
Then the king of Assyria sent Tartan and Rab-saris and Rabshakeh from Lachish to King Hezekiah with a large army to Jerusalem. So they went up and came to Jerusalem. And when they went up, they came and stood by the conduit of the upper pool, which is on the highway of the fuller’s field. 18 When they called to the king, Eliakim the son of Hilkiah, who was over the household, and Shebnah the scribe and Joah the son of Asaph the recorder, came out to them (II Kings 18:17-18 NASB).
The very Hezekiah who overlaid the pillars of the Temple of Jehovah with gold was the very same Hezekiah who cut off the gold and sent it to the Assyrian king as tribute. Had Hezekiah at this time trusted fully in the LORD, he would not have suffered this abuse to the Temple of the LORD. But he was a fallible man in a difficult situation, there is no doubt.
Then Rabshakeh said to them, “Say now to Hezekiah, ‘Thus says the great king, the king of Assyria, “What is this confidence that you have? 20 You say (but they are only empty words), ‘I have counsel and strength for the war.’ Now on whom do you rely, that you have rebelled against me? 21 Now behold, you rely on the staff of this crushed reed, even on Egypt; on which if a man leans, it will go into his hand and pierce it. So is Pharaoh king of Egypt to all who rely on him. 22 But if you say to me, ‘We trust in the Lord our God,’ is it not He whose high places and whose altars Hezekiah has taken away, and has said to Judah and to Jerusalem, ‘You shall worship before this altar in Jerusalem’? (II Kings 18:19-22 NASB).
Hezekiah now wrongly seeks help from Egypt. While he repented of his submission and compromise to Sennacherib, he commenced negotiations with Egypt, which implied treason against the king of Assyria. Thus, there was the invasion. Sennacherib imagined that Hezekiah’s real trust was in the “fleshly arm of Egypt,” but the truth was, Egypt offered no Hebrew any help. The pagan monarch also totally misunderstood what Hezekiah had done, as it regarded the “high places,” being removed. He thought that Hezekiah had seriously offended the God of Israel by doing this.
Source: II Kings 18