|The Grades of the Golden Dawn system as arranged on the natural array of the Tree of Life.|
One of the changes that Golden Dawn, and later offshoots such as the AA, makes to the traditional kabbalah is to associate each of the sephiroth to a Grade of the esoteric system. While there is some difference in the names and tasks of the Grades, the Golden Dawn and the AA can (in base form) be considered to use the same Grade system.
In addition to the ten Grades that fit neatly (in terms of diagramming) in the ten sephiroth, the Golden Dawn system has several Grades that are not properly associated with a sephirah. Instead, these Grades are associated with "gateways" to the proper sephiroth.
The first of these Grades that do not fit neatly in a sephirah is the very first Grade that a member of the Golden Dawn system experiences, the Grade of Neophyte (0=0). This Grade is associated with the edge of the sephirah Malkuth, or Petach Sha'ar "Gateway of the Gate."
The second of the Grades to fall outside of a sephirah proper is Portal which is said to be the gateway to the Grade of Adept Minor (5=6). The Grade of Portal is associated with Kenisa Sadna "Entrance to the Workshop" which is like the porchway to the sephirah Tiphareth.
The third and final Grade that is not assigned to a true sephirah is the Grade of Babe of the Abyss. This Grade is used more in Thelemic circles than in Golden Dawn, but there are some Golden Dawn Orders that do contain a ritual and course work for this Grade. Babe of the Abyss is associated with Da'ath, a pseudo-sephirah that is a combination of the symbolism and energies of the Supernals.
These three Grades, as well as their gateways, have several things in common. Each of the three Grades are probationary Grades for their respective Orders (Neophyte--Outer Order of the Golden Dawn; Portal--Inner Order of the RR et AC; Babe of the Abyss--The Third Order of the AA). Each of these Grades lay on the Middle Pillar of the Tree of Life. And each of the Grades, as well as their gateway, have symbolism related to, but not completely matching the symbolism of the Grade and sephirah that it leads into.
From the viewpoint of traditional orthodox kabbalah, only Da'ath is considered even remotely to be a real place; yet the Golden Dawn and AA use of these symbols make them real places and rest stops for students undergoing the initations of the Western Mystery Tradition.