Energy is Energy. It is neither good nor bad. It can only be free-flowing, stagnant or dense. All life is surrounded by it. Quantum physics shows us that at the lowest levels, matter is at the same time energy. The smallest particles are in fact waves of energy (quantum). We know now that energy precedes matter, just as we know that emotions and thoughts precede actions.
A healthy person will experience flows of energy freely energizing their physical body. Energy centers, known as chakras, energetic meridians and nadis, are enriched by this energetic life force. It also surrounds our auras, our energetic fields. When energy in our organs and cells are in disharmony, or have a frequency mismatch with our life force energy, or if the circulation of energetic flow in the body is interrupted, we experience disfunction or disease.
Reiki is a spiritual healing practice originally practiced in Japan, which works to heal these blockages, softening the dense areas in order to reestablish a healthy flow. The word Reiki comes from the word roots Rei, meaning the universal, spiritual, cosmic energetic essence, and Ki, meaning life force. When the Ki leaves the body, the body is therefore without life. Death meaning the absence of life, is the condition by which the Ki has left the body. Reiki is the process of channeling the spiritual source energy to our body’s energy centers by way of a practitioner. Reiki is not associated with any particular religion.
A Reiki practitioner is anyone who has received the training and attunements by a teacher who is qualified to do so. In this way, there is a lineage of Reiki practitioners since the founder, Mikeo Usui who established this method. Though Reiki in general is a practice much older than Usui Sensei himself, it is Usui Reiki Ryoho (Usui Reiki System or Method) that is most known in Western society. It is not something one can learn from a book, the internet or from audio learning alone.