Miracles of the Bible versus the Qur'an A skeptic said it is intellectually dishonest for me to believe in miracles in the Bible but not in the Qur'an. Is it?

What are some Biblical basis for not believing in every miracle, or that every miracle is from God?
The magicians of Pharaoh performed miracles, copying Moses' works when Moses was sent to Egypt to deliver Israel.


  And the magicians of Egypt did so with their enchantments: and Pharaoh's heart was hardened, neither did he hearken unto them; as the LORD had said. Exodus 7:22 [KJV]


Jesus warns that :


  Many will say to me in that day, Lord, Lord, have we not prophesied in thy name? and in thy name have cast out devils? and in thy name done many miracles (δυναμεις) ? Matthew 7:22 [KJV]


But he shall say to them :


  I never knew you: depart from me, ye that work iniquity. Matthew 7:23 [KJV]


Paul also says :


  though I have all faith, so that I could remove mountains, and have not charity, I am nothing. I Corinthians 13:2. [KJV]


It is prophesied in the Apocalypse that in the last days that which is termed the second beast and the false prophet works miracles on earth in order to encourage worship towards an entity other than God :


  And he exerciseth all the power of the first beast before him, and causeth the earth and them which dwell therein to worship the first beast, whose deadly wound was healed.And he doeth great wonders, so that he maketh fire come down from heaven on the earth in the sight of men. Revelation 13:12,13 [KJV]


So, not every miracle is of God.