The speed at which King Hezekiah move in restoring worship to Jerusalem was faster than the purification rituals could keep up with. Having invited Jews from all of the Promised Land, God granted special permissions.
Hezekiah, one of the best kings of the Jews, now comes to the throne. It was largely because of his godly mother that he turned out so different from his wicked father Ahaz. With great zeal he restored true worship to Judah.