2 Kings 20:8-11

8And Hezekiah said to Isaiah, What [shall be] the sign that Jehovah will heal me, and that I shall go up into the house of Jehovah the third day?

9And Isaiah said, This [shall be] the sign to thee from Jehovah, that Jehovah will do the thing that he hath spoken: shall the shadow go forward ten degrees, or go back ten degrees?

10And Hezekiah said, It is a light thing for the shadow to go down ten degrees: no, but let the shadow return backward ten degrees.

11And Isaiah the prophet cried to Jehovah, and he brought the shadow back on the degrees by which it had gone down on the dial of Ahaz, ten degrees backward.