Etheric - The regions of space beyond the earth's atmosphere; Upper regions of space,clear sky, air.

 

Ethereal -{Latin aetherius} Not of this world; spiritual. Not earthly, celestial.

Astral - {Latinastralis, astrum, star} Of or relating to a supersensible body believed by theosophists to coexist with and survive the death of the human physical body: an astral body.

Spiritual Realms - As with anything there are many theories about the levels of the ethereal or the spiritual realms. The most common concept comes from non-pagan beliefs, Heaven and Hell. Wither or not they exist in the ethereal realm can be up for great debate depending on who you talk to. A Christian will say yes they exist. A pagan like me, would say no. Heaven and Hell are what you make of your life here in this incarnated lifetime. You can create your own hell right here on earth. Consequently, you can create your own heaven as well.

The pagan view is based on Metaphysical principles and like all things there is a structure and balance. The ethereal realm does have it's levels of energy. But there are again many theories of how these are organized. 

Some suggest the levels of the ethereal realm coincide with the existence of the multiple universes that science believes it has proven exists. These are basically parallel universes that exist on different energy levels than ours And it's where the term multi-verse comes from.

Other say there's a more organized spiritual or supernatural range of ethereal realms. And this is what I believe. So what are these levels? All together they make up the "Divine Universe".

 

The Lower realms:
Where the essence of negativity thrives. Some suggest this lowest level is for souls who have created such evil and karma for their spirits that they have been banned by the Divine consciousness to their own realm of existence. People like Hitler and various serial killers for instance. This is also
the realm of the mythological Demons. You might look at this group as angels or spirits doing service in the negative ethers. They inhabit or are regulated to this lower energy realm. They assist with the punishment of condemned souls, or play havoc with unsuspecting incarnated souls. Many believe that "soul possession" by these Demon spirits continue even today.

The physical realms:
Where we as incarnated beings exist. (Don't limit this realm to just Earth -) 

 
The "earth bound" realms:

Where ghosts exist. Learn more about Ghosts and Spirits.

The animal realms:
Where nature thrives in spirit.

The Spirit realms:
Where spirits exist. Where we go when we leave this physical incarnation.

The Angelic realms:
"The keepers of the Divine Universe", the buffer between the intense divine energy and the remaining spiritual realms. Many believe the Beings on this level have never been incarnated.

The pure energy of the divine realms:
Where the Great Spirits exist, "The God Level". (7th Heaven).
Now even in this theory you can see how someone might interpret the top realm as Heaven and the bottom as Hell. But the connotations of what those 2 places mean in our society today don't fit in this metaphysical theory. The Divine realm isn't a place you can get into just by dying. And the lower
negative realm isn't a place you go to just because you're bad.

Navigating the Realms of Spirit:
Through spiritual evolution and enlightenment we can advance through many of these realms. Some believe our spiritual essence started out as a basic nature. Through evolution and enlightenment we progressed through those levels of animal intelligence until we evolved into human form. Others believe we, as spirits, move back and forth between human form and
animal form based on our deeds in each incarnation. This is a common Buddhist belief.

Another theory states that we exist as spiritual beings on the spirit realm and through enlightenment we progress within that realm until we reach a state of divine choice.

The choice is pretty simple, we can chose to incarnate again for the purpose of teaching others, or we can chose to move on to the next spiritual realm and enter the Divine realm. There are those who don't believe Jesus was the "son of God" but rather a soul that chose to return to physical form to teach Divinity to others. And upon his death, his spirit moved into the Divine Realm.

But within most of these theories, there is a belief that spirits never move into the Angelic Realm. But that the beings on this level assist spirits to move between the lower realms, keeping order within the Divine universe.

They also assist spirits move from the Spirit Realm to the Divine Realm when the requirements of spiritual enlightenment have been reached.

The Sub-Levels of Spirit:
Another component to some of these spiritual evolutionary theories is that each of these realms have their own 7 levels of existence. Even on the Angelic realm, these realms are described as the hierarchies and choirs.
(You can read more about this in Angels Explained).

These sub-levels need to be traversed in order to move through the levels of enlightenment. This occurs through lessons on the "interconnected realms".  In other words, we move between the lower realms learning lessons, repaying
or redeeming karma, and learning enlightenment. But through our deeds, we can also move back as well as move forward.

 

The interconnected realms are:
The Lower realms
The physical realms
The "earth bound" realms
The animal realms
The Spirit realms

As an example, if we live an incarnation on the physical realm where we commit horrid murders, our spirit will be moved to the lower realms by the Angelic forces. From here we will be forced to start over on our spiritual evolution to enlightenment. Again there are varying theories on this. We might incarnate through the animal realms again, moving from slug to eagle or wolf, and then to human form to continue our evolutionary trials. 

If we fail again, we will be taken back to the lower realm by the angelic forces and kept there a little longer next time.
Or we might be kept in the lower realm until our spirit comes to terms with what occurred in the physical embodiment. Through compassion, the Angelic forces move our spirit to the lowest sub-level of the Spirit Realm. And we are given another chance to incarnate in human form and evolve.
Many religions and belief systems have some form of evolutionary enlightenment theory.

 

Buddhists, Hindu, Native Americans, Shamanism and many
others.

 

In theory even non-pagan beliefs have a form of this theory. If you are evil in life, you're sent to Hell, if you're not, you're sent to Heaven where your deeds are reviewed before you enter the Gates of Heaven.