In times of past "The Mysteries" were truly mysterious as they were purposefully held this way. They were taught, shared and expressed to a very few. I believe at the time, there were reasons for this as all were not fully in the place to accept what The Mysteries had to offer.
There would be a community spiritual leader such as a Shaman, Wise Woman/Man who held these traditions and the memories. The passing down of information was done orally through instructional stories that led to practical application. There would be a selection process of who was to be taught in the hopes this person(s) would continue with the traditions. These select chosen ones often keep to themselves and became quite solitary individuals as they were to keep the teachings a "secret".
Times have changed and nothing is truly a "mystery" any longer. We are in a time of revelations where all things that were at one time held in "secret" are being illuminated and shared. It is a time to be part of this resurgence of knowledge and to embrace that it is available for each and every one of us.
There are still "teachers" but, our role in this lifetime is very different and truly unique than in times/lives of past. We are not necessarily sharing something that is shrouded and unknown but, we are more in the position of being catalysts in assisting to opening doors of memories to bring individuals into their own power.
The Beloved Heart Source
"Magdalene Mystery School"
The Unfolding Mysteries