A question over at Catholic Spiritual Direction:
… can you explain what exactly is a demon? Do they have bodies? Where did they come from?
A: A demon is a spiritual being of an angelic nature that has been condemned for eternity due to his rebellion against God. As pure spirits, demons are not made up of matter. Because they do not have bodies, demons are not inclined to any “sins of the flesh” (i.e., it is impossible for them to commit the sins of lust or gluttony). The sins of demons are exclusively spiritual. But they can tempt human beings to sin in matters of the flesh.
Demons were not created evil. (In fact, it is impossible for God, who is Goodness itself, to create anything evil.) Remember: demons are just “bad angels.” After God created the angels, He tested their fidelity to Him before admitting them to the Beatific Vision, the sight of His very essence. For purely spiritual beings, this “seeing” of God’s essence would be a purely intellectual vision. Some angels obeyed the divine test; others did not. Those who disobeyed were irreversibly transformed into demons and cast out of heaven.
It may seem surprising that some angels would choose to hate God. But we need to understand that those who rebelled saw God no longer as a good—as the Good—but as the oppressor of their freedom. Hate was born as their wills resisted the call of God and held fast to the decision to leave the Father’s house.
Now war arose in heaven, Michael and his angels fighting against the dragon; and the dragon and his angels fought, but they were defeated and there was no longer any place for them in heaven. And the great dragon was thrown down, that ancient serpent, who is called the Devil and Satan, the deceiver of the whole world—he was thrown down to the earth, and his angels were thrown down with him (Rv 12:7-9).
How can purely spiritual beings fight among themselves? What weapons do they use? Angels are spirits, so their battles must be purely intellectual. The only weapons that they can use are intellectual arguments. The angels gave reasons to the rebels for why they should return to obedience to God. The rebel angels countered with their reasons to support their position and spread their rebellion among the faithful angels. In this epic angelic battle, some who were inclined to rebel returned to obedience, while some of the faithful angels were seduced by the evil arguments of the rebels.
In art, demons are depicted as deformed and grotesque beings. This would seem appropriate given that demons have definitively decided on a destiny far from God. The interior loneliness in which they find themselves forever and their envy of the faithful who enjoy the Beatific Vision continually bring them face-to-face with their sins. They hate God, themselves, and all those who seek to serve God.
But not all suffer the same pains. Some angels were deformed more than others in the battle. Those who were more deformed suffer more; the least deformed suffer less. The intellects of the rebellious angels were deformed and darkened by the very reasons they used to justify the rebellion of their wills against God.
Their plight is similar to the moral debasement that humans can suffer through sin. We need to remember that we are composite creatures made up of soul and body. Aside from the sins that are proper to the body, the internal psychological process that leads a good person to end up in the Mafia or as a guard in a concentration camp or a terrorist is essentially the same as the sequence of acts of intellect and will that led to the fall of the bad angels.
Though we are body-soul composites, we as humans have only to look into our own interior life to understand how we can fall into sin. In this light, the sin of the angels becomes more easily understood.