The Devil card doesn't mean that you're evil (perhaps a little impish?), but it does signify that you're far too focused on the material rather than the spiritual realm. Anything that has to do with physical possessions or intentions that are more harmful than good is something this card will highlight. For instance, if you're more concerned with your physical appearance, you're feeling a little envious of others who have more than you, or your comments have been crueler than they should, that's when the Devil would appear. It tells you that you're leading an unbalanced life that lacks perception.
The goat (symbolic of Capricorn) depicted in this card is so faded, it's close to a "shadow" of the animal itself. This symbolizes the fate one suffers if they become lost in material possessions—as they become a "shadow" of their former self. In order to free yourself of this bondage, you must first recognize it and embrace your dark side.