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 spoken: Behold, I will cause the shadow on the stairway, which has gone down with the sun on the stairway of Ahaz, to go back ten steps.” So the sun’s shadow went back ten steps on the stairway on which it had gone down.

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