All minerals, plants, animals and intellectual animals (that is, so-called "humans"; this term is used to emphasize that ordinary people lacking solar bodies have in actuality not yet become fully human) possess lunar bodies. These bodies are also called "protoplasmic bodies" or "the four bodies of sin," and include the Physical, Vital, Astral and Mental Bodies granted by Nature. When ordinary people fall asleep and dream, they leave their physical bodies and travel in their lunar Astral and Mental Bodies.
All beings begin as essence (the undeveloped embryo of a soul or buddha-nature) clothed by Nature in lunar bodies, which mechanically evolve from the mineral kingdom through the plant and animal kingdoms. As intellectual animals at the peak of mechanical evolution, we have the opportunity to shed our inferior lunar bodies, fully develop our souls through conscious willpower and attain solar bodies not subject to Nature's laws; if we do not take advantage of this opportunity, we will again devolve back into animals, plants, and minerals, until our lunar bodies are fully disintegrated. This devolution is a painful cleansing process through which the individual essence is ultimately freed to begin again the process of mechanical evolution.
The Internal Bodies, studied by the pseudo-esoteric and pseudo-occultist schools, are common property for all of the beasts of Nature. These are the Lunar Bodies or Protoplasmic Bodies.
The laws of evolution and devolution are enclosed within the Lunar Protoplasmic Bodies.
The Protoplasmic Bodies evolve until a certain point, perfectly defined by nature; afterwards, they downwardly precipitate through the way of devolution, reverting their processes until reaching their original point of departure.
The evolution of the Protoplasmic Bodies is performed over the surface of the Earth in this cellular world.
The devolution of the Protoplasmic Bodies is performed within the submerged mineral kingdom.
It is not strange that the Protoplasmic Bodies initiate their devolution in this cellular world; however their complete devolving processes are processed within the Underworld.
The Protoplasmic Bodies can never be destroyed by the death of the physical body. After physical death, the Protoplasmic Bodies continue to exist within the molecular world.
Spiritualists talk abundantly about the perispirit, which is constituted by the Protoplasmic Bodies.
The ectoplasm (the materialization of the Lunar Bodies) has been performed successfully in some scientific laboratories. This is how these Protoplasmic Bodies have been photographed.
The embryonic soul (which every human being carries inside) is dressed with these Protoplasmic Bodies.
The devolving Lunar Bodies repeat the processes that they had experienced within Nature, yet in a reverted way. They retrospectively revive their entire human, animal, plant, and mineral past.
When the Protoplasmic Bodies return to their point of original departure (situated in the mineral kingdom that is the basic point of the scale) then these bodies are reduced to cosmic dust.
The destruction of the Protoplasmic Bodies is indispensable in order to liberate the lost souls.
The lost souls return into the original, primitive chaos. Here, they have to ascend anew until finally reaching the human state again; that is, after having repeated the very long and millenarian evolving ascension that processes itself through the mineral, plant, animal and human kingdoms.
The destruction of the Protoplasmic Lunar Bodies in the Infernal Worlds is infinitely painful. Dante symbolized it marvelously in his Divine Comedy. - Samael Aun Weor, The Narrow Way, chapter 9
What is the relationship between the lunar bodies and the solar bodies?
Whereas everyone possesses lunar bodies at birth, only initiates practicing sexual alchemy (or tantra) with a partner can come to possess solar bodies. As the product of conscious willpower rather than mechanical evolution, the solar bodies are not subject to Nature's laws, and are free to ascend to the Superior Worlds.
"No one can enter into the Kingdom dressed in the rags of a beggar (Lunar rags)." - Samael Aun Weor, The Narrow Way, chapter 33
The kingdom of heaven is like unto a certain king, which made a marriage for his son, and sent forth his servants to call them that were bidden to the wedding and they would not come.
Again, he sent forth other servants, saying, Tell them which are bidden, Behold, I have prepared my dinner: my oxen and my fatlings are killed, and all things are ready: come unto the marriage.
But they made light of it, and went their ways, one to his farm, another to his merchandise: and the remnant took his servants, and entreated them spitefully, and slew them.
But when the king heard thereof, he was wroth: and he sent forth his armies, and destroyed those murderers, and burned up their city.
Then saith he to his servants, the wedding is ready, but they which were bidden were not worthy. Go ye therefore into the highways, and as many as ye find, bid to the marriage.
So those servants went out into the highways, and gathered together all as many as they found both bad and good: and the wedding was furnished with guests.
And when the king came in to see the guests, he saw there a man which had not on a wedding garment: and he saith unto him, Friend, how camest thou in hither not having a wedding garment? And he was speechless.
Then said the king to the servants, Bind him hand and foot, and take him away, and cast him into outer darkness; there shall be weeping and gnashing of teeth. For many are called, but few are chosen. - King James Bible, Gospel of Matthew 22: 1-14
Initiates who have attained solar bodies must work very hard to eliminate their egos and their lunar bodies.
"The Lunar Bodies belong to Nature; She lends them to us, and therefore we have to return them to Her." - Samael Aun Weor, The Narrow Way, chapter 33
In a later lecture, Samael Aun Weor explained that he used the phrase “lunar bodies” in a similar way to how we call each other “human beings,” even though we are not. That is, we are being polite, but the truth is something else. He said:
“Only a human has [internal] bodies; the “intellectual animal” has no bodies. That he has a “lunar astral body” is not so. The only thing that the “intellectual animal” has inside are demons. It’s a lot of devils, but it doesn’t have more... They are the “I’s”, which penetrate and interpenetrate each other... What I said in one of my books about lunar bodies, I was referring to the egos and the three main demons that everyone carries inside, which are the demon of desire, the demon of the mind and the demon of evil will, which they act as astral, mental and causal, but they are nothing but demons. So, practically, the “intellectual animal” does not have any kind of bodies: neither solar, nor lunar, nor anything; It’s a bunch of devils that you have to turn to dust, so that the consciousness remains free and can see, hear, touch or palpate the great realities of the universe...” —How to Develop Ourselves into a Complete Human Being and Eliminate Our Defects