Historically, Ningishzida appears as the patron Dingir of King Gudea of Lagash, and has many of the characteristics of the later Thoth and Hermes, most suggestively the earliest form of the caduceus, on a votive cup from Lagash (c. 2000 BCE). Before that, he was a serpent god, having to do with magic and healing. Once associated with the underworld, he later appears with Dumuzi as a guardian of the gates of Heaven.

 

This seems to correspond very well to the mixed nature of the Serpent and to the associations with matters Mercurial, including a certain uncertainty about his original gender, as serpents in the Middle East tended to be Goddesses in Obaid (pre-Sumerian) times.

 

Esoterically, although Ningishzida manifests with a "flavor" of Fire of Earth, he is also a connoisseur of very ethereal astral spaces which barely even manage to maintain the character of Air. At the same time, once awakened, he is a powerful force for sex, fertility, and the free play of all the faculties.

 

References:

"Nin-gishzida." Encyclopedia Mythica.

http://www.pantheon.org/articles/n/nin-gishzida.html

[Accessed September 27th, 2003.]

 

"Ningizzida." Encyclopedia Mythica.

http://www.pantheon.org/articles/n/ningizzida.html

[Accessed September 27th, 2003.]