The world is full of fakes and charlatans who are out to deceive and mislead the weak. But it’s nothing new. The great prophet Isaiah addressed this problem in his day. (See Isaiah 8:19-20)
When Isaiah’s people were being told to “Seek unto them that have familiar spirits, and unto wizards that peep, and that mutter” Isaiah posed two questions: First, “Should not a people seek unto their God?” That is, why consult a fake spiritualist when you can consult God? Second, “Should they seek the dead on behalf of living?” That is, isn’t it absurd to think that the dead can instruct the living.
Isaiah then points out the only true source of knowledge: “To the law and to the testimony.” That is, the Bible is where we should look for proper instruction. He than adds this concerning anyone who would contradict God’s word: “If they speak not according to this word, it is because there is no light in them.” That is, if anyone teaches anything different from God’s word, there is no truth to what they have to say.