“When Pharaoh shall speak unto you, saying, Shew a miracle for you: then thou shalt say unto Aaron, Take thy rod, and cast it before Pharaoh, and it shall become a serpent.” Exodus 7:9
Why would Pharaoh challenge Moses to show him a miracle? I believe it is because he is assuming that if Moses’s God is really a God then He will be able to do miracles. Now, if we can just get the church to believe that again.