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: shall the shadow go forward ten degrees, or go back ten degrees? And Isaiah said, This sign shalt thou have of the LORD, that the LORD will do the thing that he hath spoken: shall the shadow go forward ten degrees, or go back ten degrees?
This verse belongs to the account of Hezekiah's illness and recovery, in which God heard his prayer and added fifteen years to his life. It records the Lord offering Hezekiah a sign that He would do the thing He had spoken, fulfilling His promise to heal him and restore him to worship at the temple. The sign offered was a choice whether the shadow on Ahaz's sundial would go forward ten degrees or go back ten degrees. Hezekiah asked for the shadow to return backward ten degrees.
Turning the shadow back could happen only by God's direct intervention. Its movement confirmed that the Lord had heard Hezekiah's prayer. In that same recovery God directed that a fig be applied to the affected part, showing that using a simple God-provided remedy is compatible with faith and does not hinder the miracle.