Matthew Poole and continuators on 2 Chronicles 30:20

20 And the LORD hearkened to Hezekiah, and healed the people .

From their Uncleanness; which it self was a Spiritual Disease, and which probably produced a Disease, or Distemper, or Trouble in their Minds and Consciences; which also had formerly brought and might justly now bring even outward Diseases upon the Body, or, at least, Guilt, which is a Disease upon the Soul: From all which the Lord was pleased now to heal them, by pardoning this their Sin, and accepting them and their Services as if they had been clean. Which it is likely God was pleased to manifest by some outward Sign, possibly by fire from Heaven consuming the Sacrifices; which was the usual Token of Gods Approbation, as hath been formerly noted more than once.