The best and most effective linkage to Inner Plane levels is the acting out of ancient legends - even the Church knew this, hence the various mystery plays.  Legends of a similar genre, as seen in Comparative Mythology, are on-going on Cosmic strata and to act out a legend links the practitioner to Cosmic activity. 

How do we know that certain areas of Cosmic activity (levels of Force) are real and ever-living? 

E.g. -  wherever (and I mean on any planet in any solar system within any galaxy) a created being harvests food, a Food God is being sacrificed.  This may be at a human level during harvest/the hunt/slaughtering/fishing, at animal level where the squirrel hoards for winter or in the domain of a  foraging creature which we can scarcely imagine millions of parsecs away!  Nevertheless it reaffirms that a specialised part of Cosmic Force governing sustenance actually exists and is Universal.  Similar examples relating to other facets of Life in its broadest sense may be just as easily discovered.

Legends were invented by our ancestors to anthropomorphise portions of Force as Deities and explain natural phenomena.  In participating in a Cosmic legend, therefore, we link with the Deities (forces if you will) within the legend.  This in turn revitalises the Archetypal Forms in our subliminal gnosis and, in a form of bio-feedback, enables us to flesh out the Archetypal images (primordial images) by material from our own conscious experiences, thus strengthening these images and our closeness with strata of Divinity (forces). 

Probably the Archetypal images are projections of Spirit (Dark Force) into the Subliminal Gnosis to form constants of Unconsciousness.  Ignore them to your detriment.  I could elaborate further but perhaps that is it in a nutshell.

This is why the observance of the various festivals and the performance of other legendary tales (e.g. from the Llyfr Coch Hergest & the Llyfr Du Caerfyrddin) to manipulate events on the material plane are found to be the most effective way of obtaining success in the outcomes of Mystery workings.

Copyright   Gareth Pengwerin