Many see the descent of Spirit into Matter as what had occurred in the story of The Fall of Man. I believe this to be the case, so what is its purpose, and what does this mean on our journey?
In my studies, I have learned that this "fall" was crucial to our development as spiritual beings. It also seems to be a common aspect of nearly all traditions of The Mysteries, and the reverse of this becomes the path for the initiate in the acquisition of higher levels of consciousness. This path of descent can be seen as:
Yod -> He -> Vav -> He / Spirit Fire Water Air Earth - The attributes of Jehovah and hence, of us.

Traveling down the Sephirot, this was the descent, so Spirit could become Matter. You will see that nearly all teachings have to do directly with traveling back upward, however the intent should not be to reject the Matter or Material Plane, but to raise it up with you on your journey so Matter can once again become Spirit, a return to the source. In this way a fully realized soul can become fully integrated with Spirit, and exist on the Material/Earthly Plane.
You will also see this in the Eastern Traditions, where Spirit enters the Crown (Sahasrara) Chakra, descends through the elementals, and comes to rest in the Base/Root (Muladhara) Chakra, and for many remains there. So in the East the goal is also to raise the Matter (Body) back up to the Crown (Sahasrara) Chakra, gaining the highest level of consciousness.
This process of course is the same in Alchemy, where the Lead is the Base/Root (Muladhara) Chakra, and through mastery of the Physical, Mental, and Emotional Planes, one can raise their consciousness to the level of Gold through the supplied Alchemical processes of Spiritual Alchemy, which is done primarily through the application of Heat/Fire/Shin.
Many of you may be attracted to a particular path, such as Alchemy like myself. However, are the Mysteries and the Mystery Schools of Alchemy, Qabala, or Rosicrucian and others different? Most Definitely not, there is but One Mystery. And I see an enormous benefit for understanding some or a great deal of each path, so one can see the patterns, the equality. Most paths contains most of the teachings needed, however, almost all have some missing pieces that another path may provide.
Wonderful series you have put together here, has really supported my understanding of these concepts.
In The Work,
Tris