@Apple Sky and
@d taylor both demonstrate an understanding of God which is little different from the pagans. After all, if the earth is flat and the sun and moon are two local light sources, it is of no consequence to pause their movement in the sky or even move them backwards. It is no great miracle at all, it is not even supernatural.
For those who understand that the earth is a massive rotating globe in orbit around the sun however, this miracle is huge, because it demonstrates God is master of every facet of His creation, suspending the very laws of physics. If God were to stop the rotation of the earth without suspending the physical laws, all life on earth would have been destroyed in moments as mountains would have collapsed and oceans rushed over the dry land.
Thus, for the globe earth, the miracles of Joshua and Hezekiah highlight for us the absolute power and majesty of our infinite God. For the flat earth, it highlights how weak and pathetic their view of God is, and how He is no different for how the pagans perceive God to be.