Practicing Reiki as a spiritual discipline is almost never discussed in any books, any websites and none of the national Reiki organisations. So prevalent is the obsession with Reiki as nothing more than a hands-on energy healing system, that its larger, more challenging but more important aspects are by and large, pretty much ignored.
It could be argued of course that even if we are focused only on using the energy healing part of the system, we’re still using it as a form of personal spiritual practice because, on a macrocosmic level, there is no ‘other’ to give a healing session to. But that’s a philosophical route we don’t need to go down as it just leads to a very laissez-faire approach to personal spiritual development.