Ka, double, khaibit, ba, sahu - what a confusing complexity of terms for what moderns simply call “soul.” Everything we know about the ancient Egyptian concepts of non-physical being come from writings like the Pyramid Texts, the Book of Going Forth, Coffin Texts, etc. These do not define terms that must have been an accepted part of the culture, but we can derive a sense of their meaning from the context of what they do, where they live, and to what they are attached. Reams and reams have been written about Egyptian ideas of the soul, but I will only give as very brief summary here, as best I understand.
shat - this is the living body; a corpse or mummified body is the khat.
ba - shown in art as a bird with a human head, I think of this as the personal identity, the personality. The ba is restless and longs for the next life, but is attached to and continually drawn back to the shat, then the khat.
ka - source, life force, “higher self,” the group spirit or energy of one’s ancestral group.
akh - the being of light that one becomes as a last step in spiritual development after death, often translated as “shining one,” or “imperishable star.”
sah - a spiritual body, sah is to akh as ka is to ba
Some people also add some more concepts to this group:
ren - one’s true name; to speak the true name of a person or any thing in the world gives one power over it.
ib - the heart, seat of individual existence, conscience, intellect.
sekhem - personal power or will
hau - unified whole of all aspects of one’s existence
Egyptians also located different qualities of the soul in various parts of the body, for example:
heart - seat of being
legs - strength
arms - ability and efficiency
genitals - creative power
mouth - entry and exit point of life
eye - inner strength, protection, knowledge
ears - understanding, compassion
Somehow, western culture began to view existence in a binary or polarized pattern, about the time the Egyptian civilization was dying. Many will not accept the veracity of anything that is not physical; others exalt the non-physical as a superior state. Egyptian cosmology, however, is all about the cycle of life, death, transformation and rebirth. Each aspect of the self is a facet of being, a step along the way of growing.
One thing the current age seems to be getting right is to recognize the hau, the whole self. But I also like the nuances of the Egyptian terms, which honor the parts of our self, defining the underlying purposes of each.
I have passed through the Duat
I have seen my father Osiris,
I have scattered the gloom of the night . . .
I have become a sah,
I have become an akh,
I have become equipped,
Oh, all you gods and akhs,
make a way for me . . . (Book of Going Forth By Day)