Like the evolution of man physcially, one's spiritual evolution may explain the level of one's beliefs.
If someone believes theirs is the Only True Relgion, don't hold it against them, they can't help it. It is the level of spiritual evolution that they have reached that determines their ideas.
Ken Wilbur, an American psychiatrist and Christian Mystic identifies a nine-stage process of consciousness/spiritual evolution. I am going to give a brief description of each. To truly explain each stage would take many pages from this blog. If you would like to learn more read Putting on the Mind of Christ, by Jim Marion. The information that follows comes from that book.
The early stages of conscious development are fairly accepted as accurate in the child development arena, and have been tested time and again in various experiments. And they match well with other suggested “soul progression maps” detailed by Mystics over the centuries.
Wilbur’s first level is known as the Archaic consciousness level. Affecting children from infancy to about the age of three, this stage is mainly physical, followed by an emotional part. For the infant, this first stage is all about sensation and impulse. The infant initially cannot distinguish itself from its mother. After about three months, the child finally realizes that it is separate from its mother physically. It take another year or so before the child can distinguish its emotions from its mother.
From a spiritual perspective, to think of the development of Stone Age people would be to see the Archaic level at work. Archeological evidence suggests that peoples of this age felt that they were apart of nature, not separate. And everything was done instinctively, based on sensory input.
The second level, the Magical level, is found in children from approximately age three to age seven. For anyone at this level, the world is full of magic and a polytheistic vision of the world (Gods, demons, fairies, etc.) rules. The child at this stage is able to learn right from wrong and gradually learns that its point of view of the world is not all that there is.
This stage is very similar to the level of consciousness of ancient polytheistic, animistic, tribal-organized people. At this level, the idea of self is a very important aspect of life. And the world is full of magic. Even today, some tribal peoples may be afraid to allow someone to take a picture of them or to learn their names so as not to give away their power to others.
The Mythical level is the third level of this map. This level is usually found in children from age seven to adolescence. The child can now distinguish itself from everything else but still holds the idea of many Gods (Santa, Easter Bunny, etc.). He or she no longer believes that he or she can do magic, but believe that God and other God-like entities can. This stage is a very “conforming” stage and the child does what its Gods (mom, dad, Santa) tell it. It is the law and order level.
The child at this stage begins to understand more abstract ideas, like understanding that the word “dog” refers to all dogs, not just the one pointed at. He or she also begins to see the world as very concrete. Everything is black and white and is taken very seriously. The child believes their parents are always corrects, as are teachers and others in authority positions. And the religion that they are exposed to (usually their parent’s religion) is the true and only religion.
For an adult found in this stage, theirs is the only true religion as well. Others who follow another religion can be seen as evil and doomed to spend the afterlife in hell unless they convert.