Help With Nightmares Of Magic?

i am a REALLY religious person, and i went to my friends house to borrow some magic kit when i was younger and thought it was cool so i brought it home. and at that same night, i had the ugliest nightmare i ever had. since then i got really careful with magic and stuff like that.
SOMEONE PLEASE TELL ME, WHAT IS IT ABOUT MAJIC LIKE CRISS ANGEL AND DAVID BLAINE, THAT IS SO EVIL.