I’m wondering if this is true?
Source
Um. I have my doubts.
First, your source seems to think demon’s And evil go together.
I don’t think hair and nails are instruments of evil…their natural parts of the body… And any other part of the body “grows a life of its own”…I mean thats basic cell biology…
Seems like dogma to me.
I hope so. I like to keep mine long and sharpened into points 
All jokes aside though, I don’t really see the connection… Plenty of people have long fingernails and demonolatry is likely the furthest thing from their mind. But, it is a good idea to dispose of fingernails and hair properly, if you feel like you’re in danger of being cursed, as they can be used as sympathetic links.
No.
Every culture has its norms and ideals with beauty. Tying things that are undesirable with things of similiar status in terms of religion is not uncommon.
Nah. I doubt it but have a kinda funny memory somewhat related
I remember a decade ago some “healer” who was a friend of my friend’s boyfriend at the time, so I wasn’t even seeking his help or advice. He just kept saying to me “wow those thin fingers…those long nails…you are evil…a devil woman!” I couldn’t stop laughing which just egged him on
hahaha. oh well that would explain a lot about my teen years.
It’s just superstition
Occult-world is similar to wikipedia its information comes from other sources, whether the sources are good or not is maybe 50/50 but what C.Wilson said is pretty much it.
In the case of the tribes in Madagascar, maybe it’s symbolic? Like with long nails in those conditions, parasites and bacteria could collect under them which results in sickness which could be interpreted as the devil🤔
Long nails aren’t very hygienic. They trap a lot of dirt which could have dangerous things in it and the best way that the ancient people could describe it was the Devil.
No wonder i keep them so long lol evil queen vibes lol. Nah i doubt it in all honesty it more likely derived from the fact that hair and nails keep growing after death, which would have been terrifying for people back then. Ahhh there vampires
lol.