Demons are usually malevolent spirits from Outside.   And when I say outside, I don’t mean outside your house.  I mean outside of everything.  Outside the galaxy, outside our universe and even outside our dimension.  They come from outside of everything we know.  We don’t know what they look like.  No one has ever seen one.  We don’t even know if they even have bodies.    So how do we know there even are such things as demons?

Simple, they possess us!
Demons come to our world as spirits.   If they have material bodies, which some demonologists say they do, they have to leave them behind.  Their matter cannot enter into our universe.  It’s to foreign, it would fall apart, explode, or the more spiritual minded among us says, God does not allow it.   Either way, a demon has to be invited.     They need permission to enter our world and then they need permission to possess our bodies.   Usually the spirit of a demon can be seen right before it takes over a host body as an inky, serpentine cloud of black smoke.  The smoke enters the body through the mouth.   This is why medieval people covered their mouths when they yawned.

What do demons want?  Who knows?  Some say they want to take over our universe, topple the Creator and assume control of our universe.  Other say they are just parasites, they just want to feed.   The one that scares me the most is that a few demented scholars suggest that they just like to play.

What we do know about demons we have learned from the possessed.   It’s inconsistent, and contradictory.    This has formed the theory that demons are liars.   I don’t think so.  I think the Outside is much larger and many, excuse the pedestrian use of the word, for no other word fits, species of demons exist.  Each species would have its own agenda, its own ‘truth’.   So May demons are telling the truth?    More research is necessary.
What is known is that demonic possession can be treated.  The possessed do not like light.  It is assumed that the Outside is a dark place and light is a new sensation to the demon.   It is also true that the host body succumbs to some sort of deterioration.    The will, the personality of the host is eroded over time.   Many are left nearly shells of their former lives, susceptible to the merest suggestion.   

A treated silver seems very helpful to force the demon to leave its host.   Unfortunately, the methods of treating this silver is a nearly lost art.    I have in my possession the Cross of St. Jerome, which I have never surrendered for scientific study for fear of never being returned.   One glance of this this treated silver cross has sent many demons scurrying back the netherworld of whence they came.
A few guarded rituals, held in locked books by a few orders of the Freemasons, have been very effective for not only exorcising the demonic spirit from the host, but also protecting an area, such as a lodge, from demonic invasion.   These, for the lack of a better term, spells, are closely guarded for fear of the demons learning them and learning to counter them.
I have read accounts of horrid men building sheaths for demons.   I do not know if this is true, for I have not as of yet encountered any of these so called sheaths.   

These sheathes are supposed to be soulless bodies, constructed from corpses of humans and even animals that are temporary homes for a summoned demon.    Who would do this, in my humble opinion, is a man not worthy of the gift of life.   This person is an abomination and as such, your grace, I would hope you would agree with my mindset that they do not deserve to breathe God’s good air.

So in response to your question, Holy Father, the answer is yes; demons do exist and are a threat.  While rare, they are extremely dangerous and I would have to vote yes to your proposal to retrieve the Nail from the vault.  I would gladly carry it in the service of our lord and savior, Jesus Christ.


Signed,
Your humble servant in the true church of St. Peter,
Father Vincent Abandonato.

Great write up.