What does 2 Chronicles 32:24-31 mean?

In those days Hezekiah became sick and was at the point of death, and he prayed to the LORD, and he answered him and gave him a sign. But Hezekiah did not make return according to the benefit done to him, for his heart was proud. Therefore wrath came upon him and Judah and Jerusalem. But Hezekiah humbled himself for the pride of his heart, both he and the inhabitants of Jerusalem, so that the wrath of the LORD did not come upon them in the days of Hezekiah. And Hezekiah had very great riches and honor, and he made for himself treasuries for silver, for gold, for precious stones, for spices, for shields, and for all kinds of costly vessels; storehouses also for the yield of grain, wine, and oil; and stalls for all kinds of cattle, and sheepfolds. He likewise provided cities for himself, and flocks and herds in abundance, for God had given him very great possessions. This same Hezekiah closed the upper outlet of the waters of Gihon and directed them down to the west side of the city of David. And Hezekiah prospered in all his works. And so in the matter of the envoys of the princes of Babylon, who had been sent to him to inquire about the sign that had been done in the land, God left him to himself, in order to test him and to know all that was in his heart.

English Standard Version (ESV)