Course Teachings provides correlating teachings from several different sources.
The different sources tend to use different terms or concepts that have the same meaning.
The "Law of One" is a source used in this writing that was given to us from extraterrestrial messengers to learn about our spirit self and world for awakening. You can learn more about "The Law of One" and its messengers at, LLResearch.org or you can purchase its books from below.
The messengers used the concept, "mind/body/spirit complex" for the term "soul". However, the term is only briefly and actually used in the "Introduction of the Law of One, Book One", indicating the sameness in the meaning of the term. See the excerpts below showing the specific use of the term "soul" from this source teaching.
*** (Carla, the contactee and one of the authors states in the introduction), "One of the concepts most central to the system of study which comes out of research into the contactee messages offered by alleged UFO contact is the concept of the immortality of our individual consciousness. There is a long mystical tradition extending back far beyond Biblical times, which posits a type of immortal soul. St. Paul in his Epistles has distinguished between the human body and the spiritual body.
Long before St. Paul’s century, Egyptian priests had the concept of the "ka" and posited that this "ka", or spiritual personality, existed after death and was the true repository of the essence of consciousness of the person who had lived the life. Egyptians, of course, made very elaborate arrangements for life after death.
*** While it is a primary priority to activate or unblock each energy center, it is also a primary priority at that point to begin to refine the balances between the energies so that each tone of the chord of total vibratory beingness resonates in clarity, tune, and harmony with each other energy. This balancing, tuning, and harmonizing of the self is most central to the more advanced or adept mind/body/spirit complex. Each energy may be activated without the beauty that is possible through the disciplines and appreciations of personal energies or what you might call the deeper personality or soul identity.
*** The transition from space/time third density to time/space third density or what you may call your heaven worlds is interrupted in many cases. Therefore, we (the "Law of One" stellar messengers) are offering ourselves as those who continue the integration of soul or spirit complex during transition from space/time to time/space.
*** Questioner: What does the large percentage of the Earth’s population, as they pass from the physical, activate? (speaking of dying here from the body)
Ra: I am Ra. ... The normal procedure, given an harmonious passage from yellow-ray bodily manifestation, is for **the mind and spirit complex** to rest in the etheric or indigo body until such time as the entity begins its preparation for experience in an incarnated place which has a manifestation formed by the etheric energy molding it into activation and manifestation. This indigo body, being intelligent energy, is able to offer the newly dead, as you would term it, soul, a perspective and a place from which to view the experience most recently manifested.
*** Questioner: Then what was the second-density form— what did it look like— that became Earth-man in the third density? What did he look like in the second density?
Ra: I am Ra. The difference between second- and third-density bodily forms .... has nothing to do with the so-called placement of the soul.
*** In conclusion concerning the soul, the "Law of One" messengers state.... "Why then be concerned with the grass that blooms, withers and dies in its season only to grow once again due to the infinite love and light of the One Creator? .... Each entity is only superficially that which blooms and dies. In the deeper sense there is no end to beingness."
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