2 Kings 20:9

And Isaiah said, this sign shalt thou have of the Lord, that
the Lord will do the thing that he hath spoken
Cure him of his disorder, so that he should be able to go to the temple on the third day:

shall the shadow go forward ten degrees, or go back ten degrees?
that is, the shadow of the sun on a dial plate; it was left to his option to choose which he would, as the confirming sign of his recovery.