During the discussions of a group comprising members of different denominations, a Catholic friend of mine stated that he had strong belief in fruitful intercession of saints. A Non-Catholic member quipped that even the devil could work miracles with the sole purpose of keeping one's focus away from Jesus. He, however, could not cite any scriptural reference in support of the statement. There are in fact, occasions where one prays for something which, if granted, has the potential of being adverse to one's spiritual well-being: for instance, a poor drug-addict praying for a jack-pot which if won, would further drag him downwards. A benevolent God would be the last one to accede to such a prayer. But, is it possible that the Devil becomes aware of the drug-addict's prayer and is able to shower him with money so that he gets trapped in drugs for ever?
My question therefore, is: According to Catholic scholars, is Satan privy to our prayers, and can he act on them?