In 1957, Father Max Thompson began working on coming up with a way to cure a demon and make them human again. His first attempt on March 7, 1957 was attended and recorded by Josie Sands of the Men of Letters and he was aided by Father Simon. The attempt was a failure, resulting in the demon escaping and the old woman who was its vessel being killed. Father Thompson continued his efforts, leading to his 19th trial on August 3, 1958 with the demon possessing Peter Kent. Having perfected his ritual, Father Thompson was able to successfully render the demon human again. Hell learned of Father Thompson's successful experiment and sent the Knight of Hell Abaddon to kill Father Thompson and stop him from using the ritual again. Two days after Father Thompson cured Peter Kent's demon, Abaddon ripped him apart, but not before he told her some of the details of the ritual under torture. After Father Thompson's murder, his records on his efforts to create the ritual went to Father Simon.
In 2013, after learning that the Third Trial is to cure a demon, Sam and Dean Winchester search the Men of Letters bunker and locate the recording made of Father Thompson's first attempt at the ritual. Their interest drawn, the Winchesters talk to Father Simon who explains the purpose of the ritual and gives them access to Father Thompson's records. From the records, the Winchesters are able to learn of the success of the ritual and how to perform it. The Winchesters initially attempt to perform the ritual on Abaddon, but she escapes after telling them of her knowledge of it. Sam then performs the ritual on Crowley in order to close the Gates of Hell forever. While Sam comes close to succeeding, Dean stops him from completing the ritual after learning from Naomi that completing the Trials will kill him. Following his near-cure, Crowley retains traces of humanity he lacked before and for a time, a human blood addiction.
In 2014, after Dean is killed by Metatron and turned into a demon and a Knight of Hell, Sam performs a variation on Father Thompson's ritual to reverse the transformation, a variation where he uses blood purified by a priest rather than confession and one that ends when the last injection is performed without the modified exorcism. Unlike the Peter Kent demon, Dean retains his demon mannerisms throughout the ritual, even as it renders him human enough to escape a devil's trap and Supernatural Handcuffs. Eventually, with the help of Castiel, Sam is able to restrain Dean once more and complete the ritual, turning Dean human again.
Procedure and Incantation
The procedure was originally invented by Father Max Thompson back in the 1950s. After 18 times failed, finally, he founded the proper formula to curing demons. It involved purifying the blood of a human. The demon is trapped in a devil's trap drawn on any consecrated ground. The purified blood is drawn into a syringe and plunged into the demon's neck eight times, once every hour. The ritual's effect is not instantaneous. Until the fourth hour, the demon is still the one in control. It was after the sixth dose that any change was visible. At the eighth dose, the person who is performing the ritual has to recite an incantation, a variation of the exorcism incantation,
"Exorcizamus te, omnis immundus spiritus. Hanc animam redintegra, lustra! Lustra!".
His palm is slit and the palm is placed against the demon's mouth. White light engulfs the demon and a second later, the demon is cured. The demon becomes human again as a result.
A variation of the ritual is performed by having a priest bless the blood for purification instead of it being purified by repenting sins. The blood is then injected into the demon eight times, but unlike the original version, this one does not require the exorcism portion with the demon becoming cured after the eighth dose. This variation of the ritual also does not seem to require an hour between doses as Sam administered two injections within minutes of each other.
Although Father Max Thompson was a little weak from losing blood every hour, the after effects on Sam were worse as he was already quite weak, due to completing the first two trials. Every dose administered to Crowley, caused his arm to glow orange and caused him pain. As a result of Sam not finishing the ritual, Crowley did not become human again but did retain human emotions and an addiction to human blood.
If the treatments are terminated for a short while, as the demon being cured gets closer to human, devil's traps and consecrated ground lose their effect on them as do binding cuffs, allowing them to free themselves.
- This ritual is the third and final trial to close the Gates of Hell.
- The way the demon is cured is similar to the way an angel smites a demon but without killing the vessel. However, when Dean is cured there is no bright flash, as there was when Father Thompson cured Peter Kent.
- When Sam cures Dean, he uses blood blessed by a priest, rather than his own purified by confession as he did with Crowley.
- Sam also doesn't say the incantation, nor does he put a bloody hand over his mouth like Father Thompson did in the original ritual.
- Dean is badly affected by the ritual, causing him great pain, either because he's a Knight of Hell or because of the Mark of Cain, possibly a combination of both.
- The ground the ritual is performed on has to be consecrated, however, it can be consecrated through a ritual rather than be preexisting consecrated ground.
- According to Castiel, this ritual is the only known way to turn a demon back into a human.
- Castiel also calls this ritual the Ritual of Purified Blood.
- In Soul Survivor, Sam mentions that the lore on the ritual says nothing about exceptions to the cure. However, there is no lore on the ritual as it was invented by Father Max Thompson in 1958.
- When asked how he was doing as the ritual was being performed, Dean described it as feeling like he was drowning in his own sweat and his blood was boiling. However, he also displayed a great deal of pain during the ritual unlike the Peter Kent (Demon) or Crowley so this may not be a usual side effect of the ritual but one Dean's more painful cure had.
- Father Max Thompson (successfully cured the demon possessing Peter Kent)
- Sam Winchester (unfinished, on Crowley, successful on Dean Winchester)
- Most fans speculated that Sam would use the ritual to cure Dean when he became a demon in Do You Believe In Miracles? This theory is proven correct as Sam does cure Dean in Soul Survivor.