Do consider: An appeal to something greater than oneself (imaginary or not) can remove self-imposed inhibitions, freeing up the reserves of will and fortitude that most would not have normal access to.
As thinking creatures we have mental inhibitors as well, often contributing a sort of color to our egos. Self-doubt, low self-esteem and confidence, negativity perceived as coming from others, fear of the unknown and untried, and even instinctual ones, again designed to preserve your life and limb.
AND NOW, TIME FOR SOME SCIENCE!
Schizophrenic patients are typically unable to filter sensory stimuli and may have enhanced perceptions of sounds, colors, and other features of their environment… is one or more voices simply screaming over the top of all the others?