II Kings 20:8-11

And Hezekiah said to Isaiah, “What is the sign that the LORD will heal me, and that I shall go up to the house of the LORD the third day?” Then Isaiah said, “This is the sign to you from the LORD, that the LORD will do the thing which He has spoken: shall the shadow go forward ten degrees or go backward ten degrees?” And Hezekiah answered, “It is an easy thing for the shadow to go down ten degrees; no, but let the shadow go backward ten degrees.” So Isaiah the prophet cried out to the LORD, and He brought the shadow ten degrees backward, by which it had gone down on the sundial of Ahaz.