Vessel
A vessel is a human that an angel possesses in order to manifest on Earth. The term vessel was first used by Castiel in 4.01 Lazarus Rising. An angel's vessel can be destroyed by an Archangel or by Lot's Salt.
Castiel: That was my mistake. Certain people, special people, can perceive my true visage. I thought you would be one of them. I was wrong.
Dean: And what visage are you in now, huh? What, holy tax accountant?
Castiel: He's a devout man, he actually prayed for this.
Castiel: This? This is... a vessel.
Dean: You're possessing some poor bastard?
– Castiel and Dean, 4.01 Lazarus Rising
The suitability of a human to be a vessel is innate. Castiel makes reference to this while possessing Claire Novak, saying that it is "in her blood". It appears that angels are tied to certain human family lineages. Michael, when he is using the young John Winchester as his vessel, tells Dean: “You’re my true vessel, but not my only one. It’s a bloodline...stretching back to Cain and Abel. It’s in your blood, your father’s blood, your family's blood.” 5.13 The Song Remains The Same
While demons can possess any human against their will in order to manifest, angels must obtain the consent of the human before they can enter him or her. However, this consent can be coerced, as demonstrated by Zachariah's treatment of Dean. Dean's continued refusal to act as Michael's vessel prompts Zachariah to torture him, Sam, and their brother Adam Milligan.
After consent is obtained, it appears that an angel may occupy a vessel for as long as necessary, though it can be forcibly removed by other angels. While occupying a vessel, the original consciousness of the human is suppressed, though it can come to the surface in rare instances. Acting as a vessel can be a trying experience. Jimmy Novak described his experience as a vessel as "like being chained to a comet". He recalls having been shot, stabbed, and healed by Castiel. Another vessel, Donnie Finnerman, suffered brain damage after his occupation. Donnie is eventually crystallized by Lot's Salt while being occupied by Raphael, who is not able to prevent or reverse his vessel's destruction.
According to Castiel in his second conversation with Dean, angels are "walking among" humans for the first time in 2,000 years. The younger Uriel in 5.13 The Song Remains The Same comments that it was against orders to take a vessel. At least two angels have been on Earth during this period: Anna Milton and Gabriel. Anna fell, cutting out her grace, and was subsequently born as a human. When she regains her grace, her body is destroyed, but is later regenerated for her to occupy as a vessel. It appears that no other consciousness was ever present in this body. Whether or not Gabriel uses a vessel has not been stated. However, given that each of the other archangels required a vessel, it seems likely that Gabriel occupies a human.
While some angels enjoy their time on Earth in vessels, other resent it. Zachariah in particular, whose vessel is never identified, despises the prospect, as illustrated by the following quote:
Dean: Oh, great. That's all I need is another one of you guys.
Zachariah: I'm hardly another one, Dean. I'm Castiel's superior. Believe me, I had no interest in popping down here into one of these smelly things. *Zachariah indicates his body.*– Zachariah to Dean, 4.17 It's A Terrible Life
When Dean and Sam see Zachariah in Heaven, they still see Zachariah as he appears in his vessel. According to Zachariah the reason they perceive him the same way in Heaven is because they're limited.
See also Angel Lore for information on powers exhibited by angels while on Earth.
True Vessels
The term "true vessel" is used several times to described someone preordained to host an angel. It is particularly applied to the vessels of Michael and Lucifer.
Archangel Vessels:
- Dean Winchester was predestined to be Michael's vessel. Zachariah tells Dean that he is Michael's Sword.
- Sam Winchester was predestined to be Lucifer's vessel. According to Castiel, to truly contain Lucifer's essence, his vessel must be fortified with demon blood. Castiel states that Nick, Lucifer's temporary vessel, is "drinking gallons".5.21 Two Minutes To Midnight. This appears to be a primary reason behind Azazel's work with the Special Children, and Sam in particular.
- Donnie Finnerman was the vessel for Raphael. Donnie was a civilian of Maine and a mechanic prior to his consent to Raphael. Balthazar destroyed Raphael's vessel using Lot's Salt.
Angel Vessels:
- Jimmy Novak is the vessel for Castiel. While he initially consented, Jimmy is keen to resume his life with his family after Castiel is returned to Heaven. He does resume his station as Castiel's vessel. Jimmy, unlike Dean, can hear Castiel's "true voice".
- Claire Novak is Jimmy's daughter and is briefly a vessel for Castiel. After Jimmy is shot by a demon possessing his wife, Castiel possesses his daughter Claire. Jimmy, near death, begs to be allowed to take her place. Castiel agrees.
Plan B Vessels
Plan B vessels are vessels that angels use for short periods of time, or as a last resort.
Plan B Vessels:
- Nick lived in Pike Creek, Delaware. Nick's wife and child were killed by a robber who broke into their house. He later consents to be Lucifer's Vessel when Lucifer promises to help him get justice for his family. Lucifer later tells Sam that Nick is not the ideal vessel and can barely contain him. Nick was dispossessed in 5.22 Swan Song.
- John Winchester acts a Plan B Vessel for Michael in The Song Remains The Same. Michael reveals to Dean that suitability runs in the Winchester blood-line, enabling him to use John as a "Plan B" Vessel.
- Adam Milligan acts as an alternate true Vessel for Michael. In 5.18 Point of No Return, Zachariah tells Adam he will be a vessel for Michael in place of Dean, although his plan is to use Adam as bait in order to trap Dean into saying "yes" to Michael. Castiel says that Adam being used as Michael's vessel is a possibility, since he is of John Winchester's bloodline. In 5.21 Two Minutes To Midnight, Castiel tells Dean, Sam and Bobby that Michael is currently using Adam as his Vessel. In Swan Song, Michael does use Adam as a vessel for his final confrontation with Lucifer.
Other Uses of Humans by Angels
Lucifer used a dead nun as a mouth piece to communicate with Azazel at St. Mary's Convent.
Prophets are also a method through which Heaven communicates with humanity, but they are not physically possessed by angels. Chuck Shurley is a prophet.
