“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?’ ‘It is a simple matter for the shadow to go forward ten steps,’ said Hezekiah. ‘Rather, have it go back ten steps.’ Then the prophet Isaiah called on the Lord, and the Lord made the shadow go back the ten steps it had gone down on the stairway of Ahaz.” (2 Kings 20: 9-11, NIV)
As a disciple of Jesus, it is best that we not seek signs and affirmations from the Lord because, as the scripture says: “We walk by faith, not by sight.” (2 Corinthians 5:7)
But. . . when we persist in seeking a sign from God, we need to take the boldest, most audacious course so that we will know, for all time, that it was the Lord God — not coincidence, circumstance, or good fortune — that made it all happen.
And having been given a front-row seat to the faithfulness and magnificence of our heavenly Father, we should be convinced — forever — of His love and faithfulness; returning as necessary to the place where God revealed Himself faithful and true, but never again needing a divine sign.
Remember the divine visitations, and God’s answers to our audacious prayers, and the desire for new affirmations from God will be satisfied by the memory of our experiences. – Luther
Daily Encouragement 
This is true. We don’t dictate to God how He will answer our prayer.
Just don’t make mention of it in a cessasionist congregation (a la John MacArthur), or every sermon will harp against it until you leave.