"Your prophets...have not exposed your iniquity so as to restore you from captivity." (Lamentations 2:14)
The mark of a false prophet is not so much what they are saying, but what they are not saying. And even when they do say some of these things they don't say enough (see the "so as" above). That is what makes him so dangerous. Everyone would run from a wolf in wolves' clothing. But he doesn't look like a wolf, he looks like a sheep (Matthew 7:15). It's a good thing to keep in mind that the Devil doesn't actually have horns. He can easily appear as a fine preacher who is versed in theology.