Acts 19:18-19 ESV Also many of those who were now believers came, confessing and divulging their practices. (19) And a number of those who had practiced magic arts brought their books together and burned them in the sight of all. And they counted the value of them and found it came to fifty thousand pieces of silver.
Magic is an attempt by man to direct and manipulate the spiritual realm. By means of incantations, spells, potions and other methods that are really witchcraft (forbidden by the Lord), practitioners of these dark deeds believe they can assume God’s role and bring about outcomes of their liking. These evils have no place in the life of the Christian, as the new Christians in Ephesus recognized immediately.
Much of what parades as Christianity is actually superstition and magic. Prayer becomes a christianized form of incantation (remember Jesus told us that we are not to pray like the Gentiles with meaningless repetition). Satan and demons are supposedly rebuked and defeated by assorted formulas that allegedly are derived from the Bible. They are not.