My friend told me about this woman that is staying with him and his mother. Apparently she is the healer from China. He was telling me about watching her conjuring water into a glass. He says there was nothing in the glass and then suddenly there was. He says that the woman claims to get this power from a goddess. I'm worried about my friend because he starting to believe in this woman's claims of obtaining powers from a goddess. My friend is atheist, so I think this makes him more vulnerable to deception. My first suspicion was that this woman is Wiccan, but I couldn't get clarification on that. What should I tell my friend about this? It could all be some magic trick for all I know, but demonic magic doesn't exist anymore, does it? What should I tell him? Thanks a bunch!
"The coming of the lawless one is according to the working of Satan, with all power, signs, and lying wonders, and with all unrighteous deception among those who perish, because they did not receive the love of the truth, that they might be saved" (II Thessalonians 2:9-10).
Satan's power is in deceit. He doesn't have the ability to do true miracles. Thus, this woman is nothing more than a capable magician who is using her abilities to spread a lie. A quick search shows that there are magic trick methods for making liquids appear in an empty glass.
You are correct that skeptics are the most susceptible to con games because they assume they are hard to fool, so when faced with something they have no explanation for, they tend to assume it had to be something supernatural.
Tell him that according to the Bible, there is no other God than the one God. And He states that He is no longer giving out miraculous gifts (I Corinthians 13:8-10). Any claims of special powers from some other so-called god or goddess is due to trickery. He may not believe you, but he'll remember what you said later when what you said turns out to be the truth.