II Kings 22:20

"'"Surely, therefore, I will gather you to your fathers, and you shall be gathered to your grave in peace; and your eyes shall not see all the calamity which I will bring on this place."' So they brought back word to the king."

(God showing His immense mercy. After Hezekiah came Manasseh and Amon; both of which were terrible kings. But then Josiah came along, and it's not entirely clear that he became good because he had the book of the law read to him, but Josiah was the final good king of Judah. Nobody else after him followed God.)