A soul is the spiritual life essence of a person, which resides within a physical body while the person is still alive. After their physical body dies, or is destroyed, their soul continues to exist, and typically moves on to an afterlife. After death, they can refuse to move to an afterlife, and remain on Earth as a ghost, where they will eventually be killed, thus will the soul be reaped, and will either be taken to Hell or Heaven. If they go to Hell, they will end up being tortured into a demon.
When God created humans, he gave them a spiritual essence or soul, so that after their physical bodies perished, they could move on to either be rewarded or punished, depending on the life they chose to lead. Eve, the Mother of All, created monsters whose souls function similarly, but are destined instead to another dimension.
In the Natural Order, human souls are transported to the afterlife by Death's servants, Reapers; however, the reaper Tessa refused to tell Dean on more than one occasion where she takes them. Known destinations of souls are Heaven, Hell, and Purgatory. However, when Metatron closed Heaven, reapers lost their ability to teleport, and so the human souls were stuck in the Veil, waiting for its reopening. Ever since the Angels have started using the Heavenly Portal, reapers are able to take worthy souls into their Heaven. It is unknown if the damned souls are being taken to Hell, as the reapers still don't have their wings. It is possible that they are using Devils Gates to take them to their afterlife, or perhaps Demons are using their Hellhounds to do complete the task.
Souls are magical by nature and could be used by several creatures to cast spells or to increase their power. They are said to be impermanent and immune to harm. Death claimed that not even a being as powerful as him could break a soul apart, however it is shown that the inner key to oz is able to accomplish this feat, showing that it can, in fact, be done to some degree. It should be noted that while separated, they still shared a link that whatever physically happens to one happens to the other one.. According to Henry Winchester, a damaged soul could heal in due time. Usually, souls leave their vessels when they die, being taken to their final place, but they can be removed by force, leaving their owner's soulless. However, it seems souls have a link to their vessels, when removed, the souls return to them (if they are still alive) when they have the chance to do it.
In exchange for a soul, Crossroad Demon's will grant humans any desire they wish. Once the exchange was completed, the demon would give the person ten years before they came to collect. It can be as little as one year (Dean's deal) to as long as twenty-five years (Becky's possible deal). Either way the demon has to collect and send the soul to Hell.
Both angels and demons can use souls to gain more power. Castiel used Bobby Singer's soul to heal himself; he also used the power of 50,000 souls to blast Raphael, effectively starting the civil war in Heaven. Angels are also able to absorb and transfer memories from souls. When Castiel opened a portal to Purgatory using a ritual, he absorbed the souls of every monster there and the power he gained from them was enough to easily trap and kill Raphael. The souls from Purgatory also made Castiel immune to the deadly effects of an Angelic Blade. With his own power drastically augmented, Castiel claimed the title of God. It is also shown that Eve can draw power from the souls in Purgatory, calling it "her supply". After the Grigori Angels turned away from Heaven, and were almost completely destroyed, some of them began to slowly feed on human souls, gaining power. This slowly damaged their soul, which could not be healed by other Angels. However, after the victim is dead, should their soul go to Heaven (if any of their soul remains intact), they appear to return to normal, fully healed.
To preform certain spells, one must tap energy from their soul. It will eventually heal, and retain full power, so that the spell caster may preform the spell again. An example is the time traveling spell. This spell was introduced in As Time Goes By, when Henry Winchester traveled to the twenty-first century through a closet. The body can be made uninhabitable for a soul by use of a spell, that requires the person to commit patricide. According to Balthazar who suggested this to Sam, "You need the blood of your father, but your father needn't be blood." One could kill not just their father but also a father figure for the vessel to become scarred.
It has been shown that you can split a soul into two, making them seperate, yet identical, beings. To accomplish this, you need extremely powerful magic, as even Death claims that he can't do it. An example of this is the Inner Key to Oz. This key can unlock a persons soul, allowing you to split it into seperate persons, generaly seperating the good from the bad. Although the souls are now seperate, their bodies are still connected, so if one of them is damaged, so is the other. This split can be reversed by using the key again.
Types of SoulsEdit
Human souls are the spiritual essence of a person, which typically reside inside a physical body. After that person dies, should they choose to move on, a reaper will take them to either Heaven or Hell, depending on how they lead their life. The soul allows the body to feel emotions, such as happiness, sadness, and remorse, and for an unkown reason, it makes it so that humans need to sleep.
Demons are human souls which have been twisted and tortured until they are nothing but a cloud of black smoke. This occurs when a human soul goes to Hell, either by making a deal, witchcraft, or leading a bad life. They will be tortured by other demons, until they become one themselves. To manifest on Earth, demons have to posses the bodies of humans, and use them as vessels. As their soul is twisted, their emotions become corrupt, where they no longer feel sympathy or empathy. They also gain supernatural powers, which they can use in Hell, or while possessing a vessel on earth. Using the Demon Curing Ritual a demon's soul can be returned to its original human state.
Ghosts are human souls that refuse to move on to an afterlife, and remain on earth. They typically reside in The Veil, but with enough strength they can manifest in the physical plane, usually in the form of their past bodies. Staying on earth usually darkens the soul, so that it becomes a violent spirit. Like demons, they are also able to possess humans to accomplish things. When they are put to rest, a Reaper takes them to where they belong.
It was revealed in Sacrifice that when an angel loses its grace, it changes its form, and becomes a soul. This presumably allows them to feel more human emotions, as angels typically don't feel them. When an angel gains a soul, it can move on to an afterlife, such as Heaven or Hell, after it dies. It is presumed that an angel can sell its soul after it gains one. It is currently unknown if an angel soul can be turned into anything else, such as a demon or monster.
Monsters are humans that have been tampered with, and altered by Eve. It has been shown that not only are their physically bodies different than humans, but their souls are altered as well. When a monster dies, its soul goes to neither Heaven nor Hell, but instead goes to Purgatory.