Adam Clarke on 2 Chronicles 29:36

And Hezekiah rejoiced - Both he and the people rejoiced that God had prepared their hearts to bring about so great a reformation in so short a time; for, it is added, the thing was done suddenly. The king's example and influence were here, under God, the grand spring of all those mighty and effectual movements. What amazing power and influence has God lodged with kings! They can sway a whole empire nearly as they please; and when they declare themselves in behalf of religion, they have the people uniformly on their side. Kings, on this very ground, are no indifferent beings; they must be either a great curse or a great blessing to the people whom they govern.