The Celtic Reiki method was pioneered by Martyn Pentecost, a British therapist and personal development mentor. Initially taking the approach of forming a synthesis between Reiki practice and Celtic philosophy, the system used 18 original essences (the vibrations of trees) and a handful of methods derived from Usui Reiki practice. This foundation was evolved by the originator and other Celtic Reiki Masters over several years, until in 2009, Pentecost re-worked the system to include multiple layers of practice.
At this point, Celtic Reiki was viewed more as a form of communication or ‘Lost Language’, although rather than a verbal communication, this was more of a sharing or guiding back to wellbeing. Energy was no longer seen as projected or ‘given’ - it was now seen as experienced in the same way as we glean knowledge from a conversation. Essences came to represent the perspective, or viewpoint of a particular species of tree, or type of mineral, etc. These possessed their own vibrations, in the same way that sound has a vibration, however, the vital aspect of the Essence ethos is now in the expansion of perspective, rather than the vibrations it produces.
Celtic Reiki Realm Mastery consists of different experiences and areas of knowledge, which combine into a powerful form of treatment style, method of spiritual growth, and personal-development system. These consist of: Essences, Techniques, Realms, Mystics, Lores, Orientations, and Calibrations.