2 Kings 20:8-11

8And Hezekiah said unto Isaiah, What shall be the sign that Yhwh will heal me, and that I shall go up into the house of Yhwh the third day? 9And Isaiah said, This sign shalt thou have of Yhwh, that Yhwh will do the thing that he hath spoken: shall the shadow go forward ten degrees, or go back ten degrees? 10And Hezekiah answered, It is a light thing for the shadow to go down ten degrees: nay, but let the shadow return backward ten degrees. 11And Isaiah the prophet cried unto Yhwh: and he brought the shadow ten degrees backward, by which it had gone down in the dial of Ahaz.1