2 Kings 20:9-11

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