The Ancient Egyptians believed these 9 parts of the soul are what helps guide us to eternal life.
The Khat is the physical body, and vessel for the rest of the soul to live in while on Earth. Part of the reason mummification existed is due to the Khat. By preserving the physical body, the Ancient Egyptians believed they also preserved part of the soul. They would bring food and drink to the tomb, as offering for the other pieces of the soul to find. If the body were to be destroyed by any natural occurrence then a painting or statue of said person would assume the role.
The Ab is your heart, the source of good and evil, defining one’s character. It was considered the home of human emotion, as well as the center of all thoughts and intentions. The Ab served the part od a person used to gain access to the afterlife. After a person died, the soul would be met by the God Anubis, who took them to be judged. The Ab would be measured to the heaviness of sin on a scale against a feather of truth by the God Osiris and Goddess Ma'at. If your Ab weighed more that the feather, it would be fed to Ammit, a demon, and the soul would cease to exist. It it weighed less, the soul was deemed worthy and led to the afterlife.
The Ba is a souls personality, or spiritual consciousness. It is potentially the closest that the Ancient Egyptians had to modern ideas about what a soul is. The Ba is made up of everything that makes a person unique. It is your spiritual guide that doesn't become influenced by your body, mind, sense, or anything youo think you know. The Ba works to advise your heart, guiding you throughout your life. It is your consciense. It is also the piece that could travel between the heavens and earth, between afterlife and corpse, and may bring you information or advice from the Divine. The Ba is the piece of you soul that delivers your Ab to the hall of judgement. And make no mistake: it stays rational and uninfluenced by outside factors. When Ab is being weighed for judgement, the Ba will expose every time you decided not to listen to its advice.
The Ka is the vital spark, or physical consciousness. It is the distinguishing factor between the dead and the living, breathed into the body at the time of birth. Working with the Ba, the Ka is considered one of the closest translations of what a soul is to modern descriptions. While the Ba is the bit that advises your heart, the Ka is the bit that takes care of your body. Some modern translations call the Ka your automonic nervous system. It regulates things like your hear rate, digestion, pupillary responses and sexual arousal, as well as epigenetics. That means it imprints all of your experiences onto you rDNA and passes them down to future generations. Essentially, it tracks and records your generational gifts and traumas. The Ka is the piece of the soul that absorbs food offerings after the Khat/body dies.
The Shuyet is your shadow self; the shadow of the soul. Shuyet was ever present and, like the Ba, helped to identify a persons unique traits, strengths and abilities. Unlike the Ba though, Shuyet identifies the aspects of the personality not typically seen. While all may share a common source, each person possesses a unique Shuyet. Egyptians alos believed that the shadow self was linked to death, as the shadow was considered a servant to Anubis. After death, some people were buried with a "shadow box", which gave the Shuyet a place to inhabit after the Khat was laid to rest.
The Akhu is the transformed self, the magical union between Ba and Ka, which would become this enlightened immortal being after death. This enlightenment could only be possible is the correct funerary rites were performed, thus mummification was practiced. Akhu has been translated as "spirit" and is the highest self, or ones light body. It is the most Divine aspect of a person since it is the entirety of the Universe within them. The Akhu is connected to infinite intelligence, and the so called "Akashic Record" of all human knowledge. Unlike the other parts of the soul that linger, the Akhu did not. Spell 474 of the pyramid text exclaims “the Akhu belongs to heaven, the body to earth” and so the Akhu would enjoy eternity among the stars with the gods. It is the part of the soul that could reconnect to loved ones by appearring to them in dreams. It is the state that every beginner spiritualist seeks to acheive, yet can never be achieved through desire.
The Sahu is the will, or spiritual body, and a further aspect of the Akhu. After the soul was deemed worthy of the afterlife, the Sahu would seperate from all other parts of the soul. Similar to modern ideas about ghosts, the Sahu was said to haunt people who had wronged them in life, and worked to protect its loved ones that remained on Earth. The Akhu could appear to a person in their dreams, but Sahu could appear outside of dreams. It is considered the physical manifestation of a person's will, acting outside the body. It is what is inside a persons heart, expressed in a physical form."Sahu" can be lossely translated to "judge" and that's exactly how it does it's work; The Sahu manifests the world around them by judgung the persona heart and truest desires, and brings signs from the Divine onto the physical plane.
The Sekhem is the highest form, or life energy, and another aspect of Akhu. The Sekem is the vital life energy of the individual, similar to the Ka. Sekhem would be present in the afterlife, after judgement, as well as during life. During life, it could be used to control the physical surriundings and outcomes of a person and their actions. Like Akhu, Sekhem didn't live in the Khat, but remained in the stars with the Gods. Kememtic Spirituality teaches that Ptah, a creator God, breathed Sekhem energy into a person at birth. At first, it is formless, until Ptah createst the most perfect version of each human based on their unique earthly form. It is said that on the day of judgement, you will meet your Sekhem and see in it everything that you could have been. If you had lived a life of balance, and righteousness, when you meet Sekhem, you meet your twin. If you had lived unbalanced, in chaos and disorder, your Sekhem would be a stranger to you.
And finally, Ren was one’s secret name. Stories say the Ancient Egyptians were given true names at birth, a name kept secret to everyone but the Gods. Throughout life, people were only known by a nickname, since the Ren was believed to be an important and powerful part of the soul. It was said the a persons Ren contains the ability to destroy a person and their soul forever, so living by the nickname was a protection for the soul. A Ren would continue to live as long as that name was spoken. As long as the embalming process was done correctly, a persons Ren meant that the soul would live on for all eternity.