Isaiah 38:7-8, 22

“This shall be the sign to you from the LORD, that the LORD will do this thing that he has promised: Behold, I will make the shadow cast by the declining sun on the dial of Ahaz turn back ten steps.” So the sun turned back on the dial the ten steps by which it had declined.

Hezekiah also had said, “What is the sign that I shall go up to the house of the LORD?”