Yeah but... 'spiritual' doesn't need to have any connection with religion - gods, devils or inbetweenies. Surely it's about connecting with a space that isn't easily described. I have my spiritual dimension, but it's by no means religious.
I've certainly experienced some wonderful head spaces - but as Entropy Tango intimates, there's no predicting when or how they might happen. They do or they don't, and if they don't, there'll be all kinds of other incredible things going on.
I don't think pain needs a purpose. People take or desire to take pain for all manner of reasons. It may be because as a sub or slave, it's being asked of you; it may be because the particular application connects directly to your groin, or indeed to the cerebral equivalent. I just like it, spiritual portal or not.