Magic is "The pretended art of influencing events, and of producing marvelous physical phenomena, by processes supposed to owe their efficacy to their power of intervention of spiritual beings..."
Except, if God performs a miracle, he's not pretending to perform it, he is performing it. So God, by definition, cannot engage in magic. If he exists. If he doesn't exist, then he can't do magic or anything else. But the use of the term "magic" here begs the question, as do most uses of the Argument from Tendentious Terminology." Or should I call it the Fallacy of Tendentious Terminology.