| Card fifteen of The Major Arcana of the Tarot
Somewhere along the line someone got it into their head that the Devil was a liar, and that his lies were the source of his evil and his power. But here's the truth: The Devil doesn't have to lie -- and that's why he's dangerous. People lie to themselves and keep secrets from those around them. People are flawed, and a person will not freely bare all of their flaws at once because we, as humans, just aren't trusting, accepting, and understanding enough of each other to accept everyone else for everything that they are. Every once in a while you get it: unconditional love -- the state of accepting another person wholly for what they are. But that's the exception rather than the norm. Likewise sane people don't go around pointing out the flaws in others. First of all, it's cruel and hurtful. More importantly, though, it invites retribution. After all, if we say something cruel of our closest friends, we give them a reason to retaliate.
The Devil, though, is evil. Everyone knows he's evil, especially him. He doesn't need to lie to people about what he is, doesn't need to hide from anyone and, most of all, doesn't need to be ashamed to admit to any flaw someone wants to pin on him. Sticks and stones may break his bones, as the saying goes, but words truly will never hurt him. This renders The Devil virtually unmanipulable -- he has no strings to pull, no leash to pull him with, no deep dark secret that someone can reveal about him that he wouldn't freely admit to. Which all goes by way of saying, when he starts pulling up other people's secrets, there's no way to pull back at him. Sure, you can point to everything he's done and show how atrocious it is, but he'll admit all of it. He can also point out the worst flaws of others, leaving them emotionally exposed, without fear of retribution -- all his dirty laundry is already spread across the lawn.
The Devil has no morals because he cares about nothing except exerting his power over others, bending the world to his will. The devil wins every bargain he makes, because he changed what someone would have done if he hadn't dealt with them; any price he could pay is worth that, and the material world means nothing to The Devil. After all, it will all pass away. What really matters, to the Devil, is how much he can control what's here right now -- not how long he can hold on to what he already has.
And yet, in Judeo-Christian Mythology, it was The Devil who first saw the will of god as something apart from himself, and tried to change it. It was the Devil that led Adam and Eve to first see themselves for what they were, and to see the world in terms of good and evil. The Devil is at the heart of human consciousness: the faculty by which we define ourselves in terms of our actions; we act, we see the world change, and we see ourselves as the cause of that change. The devil chained Adam and Eve to his will through manipulation, seeing the effects of his actions grow in scope, and he saw himself as greater. Whenever we see ourselves as the power and scope of our actions and our ability to cause change, the devil is truly the one with the control -- we're just a link in his chain. | 
