2Kings 20:8-11 (NIV)
Hezekiah had asked Isaiah, "What will be the
sign that the LORD will heal me and that I will go up to the
temple of the LORD on the third day from now?" 9
Isaiah answered, "This is the LORD's sign to you that
the LORD will do what he has promised: Shall the
shadow go forward ten steps, or shall it go back ten
steps?" 10 "It is a simple matter for the shadow to go
forward ten steps," said Hezekiah. "Rather,
have it go back ten steps." 11 Then the prophet Isaiah
called upon the LORD, and the LORD made the shadow
go back the ten steps it had gone down on the
stairway of Ahaz.