“Enq: A truly delightful picture! But tell me, do you really expect all this to be accomplished in one short century?
Theo: Scarcely. But I must tell you that during the last quarter of every hundred years an attempt is made by those “Masters”, of whom I have spoken, to help on the spiritual progress of Humanity in a marked and definite way.
Towards the close of each century you will invariably find that an outpouring or upheaval of spirituality – or call it mysticism if you prefer – has taken place.
Some one or more persons have appeared in the world as their agents, and a greater or less amount of occult knowledge and teaching has been given out. If you care to do so, you can trace these movements back, century by century, as far as our detailed historical records extend.”
H. P. Blavatsky
The Mark Of God: Understanding Your "I AM Presence" 