'Shadow' in the Bible

Isaiah said, "This shall be the sign to you from Yahweh, that Yahweh will do the thing that he has spoken: shall the shadow go forward ten steps, or go back ten steps?"

Hezekiah answered, "It is a light thing for the shadow to go forward ten steps. Nay, but let the shadow return backward ten steps."

Isaiah the prophet cried to Yahweh; and he brought the shadow ten steps backward, by which it had gone down on the dial of Ahaz.