Just using their "analytic" system of thinking instead of their "intuitive" thinking can temporarily decrease people's religious belief.
The findings, Gervais says, are based on a longstanding human psychology model of two distinct, but related cognitive systems to process information: an “intuitive” system that relies on mental shortcuts to yield fast and efficient responses, and a more “analytic” system that yields more deliberate, reasoned responses.
“Our study builds on previous research that links religious beliefs to ‘intuitive’ thinking,” says study co-author and Associate Prof. Ara Norenzayan, UBC Dept. of Psychology. “Our findings suggest that activating the ‘analytic’ cognitive system in the brain can undermine the ‘intuitive’ support for religious belief, at least temporarily.”
I believe that .. it worked for me.