Jesus & Mo: what if we classified religious belief as a mental illness?

I think it is. Tell me how it's not a mental illness, when you have all of these people performing all these rituals, killing people, giving massive amounts of money to fakirs and charlatans, changing their lives this way and that, whispering to themselves beseeching an imaginary being to do something? All that activity just to accomodate a fantasy? It's a maladaptive coping mechanism. Believers may be able to function in the real world even with this fantastical idea in their heads, but that doesn't make it any less a mental illness.