Guf

Guf (ガフ), in Neon Genesis Evangelion, encompasses two separate but intimately connected items: the Chamber of Guf, and the Doors of Guf.

Chamber of Guf

The Chamber of Guf (ガフの部屋, GAFU no heya) is mentioned twice. In Episode 23:

RITSUKO: Yes, they're human. The Evas do not intrinsically have souls, but they have human souls embedded in them. They were all salvaged. The only vessel that contained a soul was Rei. She was the only one born with a soul. The Chamber of Guf was empty, you see. These things here that look like Rei have no souls. They're just vessels. That's why I'm going to destroy them. Because I hate them.

In Episode 26':

Fuyutsuki: The Chamber of Guf (Hall of Souls) has been unsealed... Has the door to the world's beginning and end finally opened?

Other than these brief mentions, there is no full explanation given. The Chamber of Guf is a term from Kabballah. It is said to be the place where all souls emanate. For more information, see here. However, unlike in the Kabballah, the version of the Chamber of Guf in Evangelion does not have Religious connotations. It is merely the name for the origin of all souls, which seem to exist within both Adam and Lilith

Doors of Guf

The Doors of Guf (ガフの扉, GAFU no tobira), are mentioned directly in Episode 21' and heavily alluded to in Episode 26' ("The Chamber of Guf has been unsealed. Have the doors to the world's beginning and end finally been opened?"). In the case of the latter, the actual term "Doors of Guf" appears in the script and designates the vulva-like apertures that open on Lilith's palms to receive souls. Out- and in-doors to Chamber of Guf; Adam; maybe the harpies create "artificial" ones on Eva-01 by skewering her palms, Seele seems to make a big deal out of that after all.

References

Remember to include SAUCE on Judaic lore stuff!

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