We all have a foot in two worlds. Two realities. There is the internal world, the one which exists only between your ears. Your conscious mind. Your soul. Your being. You, and only you, decide what gets in, what stays, and what goes. In the internal world you are all powerful, writing all the rules, directing all your actions. For all practical purposes, King of your own castle.
Beliefs can easily make a person a mental cripple. Speaking as a person born and raised in a cult.