The Human Soul
There are several different aspects that make up the human soul. The aura, the light body, the chakras, the ethereal double, [the ghost that takes on the image of the physical body], and the intelligence/consciousness. The human soul is also made up of the elements fire, earth, air, water and quintessence.
In doing research, I have found major discrepancies among authors as to the specific aspects of the KA, the BA, the AKH and the SAHU- the parts of soul as defined by the Ancient Egyptians. From what I can gather, the real meaning of the Egyptian concept of the "REN" is the individual vibration of the soul. This has to do with the Egyptian Kabbalah (KA BA AKH). The original Kabbalah was Egyptian and the purpose was meditation upon the different aspects of the soul, both separately and together in combinations. This is very, very advanced.
The human soul can at will be divided during meditation. This is what occurs with deliberate astral projection or involuntary "out of the body" experiences. Just as the soul can be divided, it can be reunited at will. The soul can be merged with the soul of another person.
The aura can be expended and contracted at will. It can be programmed to attract or repel anything at will. The aura can be programmed by will to act upon the aura of another for better or worse.
Each aspect of the soul can be meditated upon separately and empowered. Each aspect can invoke and hold each of the elements. This is very advanced and can be dangerous if one does not know what one is doing.
The images below illustrate two main parts of the soul. Bear in mind, the light body is shapeless. Though both illustrations are white light, these bodies can be of any color and can change color as to moods, health, emotions and so forth. They can also be of more than one color.
The above, I write from my own direct experiences and not theory.