I hear some say with obvious conviction that there is no negative spiritual enteties, or a variation where you only need to think positively then nothing can touch you.
Like many other newfangled "certainties", this is a modification of an ancient knowledge, which reads as follows: For something to really be able to hurt you, you have to be afraid.
A typical normal person has a certain resilience to negative experiences. From name calling to a real spiritual entities trying to find their way in. To be afraid, or to feel real fear and horror are much less spiritual resilient against adverse events than those who stands firmly on the ground.
But it is a misunderstanding, and I suspect that it is also sometimes a mischievous distortion to claim that just because you repress or doesn't believe in evil, you are thereby protected from it. It is a bit like trying to walk blindfolded into a busy street and believe you are protected simply because you don't see the traffic.
"Faith can move mountains", not stupidity.