2 Kings 20:8-9

And Hezekiah said to Isaiah, “What shall be the sign that the  Lord will heal me, and that I shall go up to the house of the  Lord on the third day?” And Isaiah said, “This shall be a the sign to you from the  Lord, that the  Lord will do the thing that he has promised: shall the shadow go forward ten steps, or go back ten steps?”
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