2 Kings 20:10 (NIV)
"Rather, have it go back 10 steps."
Isn't it amazing how much the Lord puts up with us? Sometimes, we do put the Lord to a foolish test and He encourages us to do so. We're not convinced when God does "ordinary" miracles, we want the Lord to perform "extraordinary" miracles, while conveniently forgetting that all miracles are extraordinary.
Like Hezekiah who wanted the shadow to retreat, we do make unusual requests to the Lord and He gladly obliges to strengthen our faith.