A Textbook of Theosophy – C.W. Leadbeater (1912)

We often speak of Theosophy as not in itself a religion, but the truth which lies behind all religions alike. That is so; yet, from another point of view, we may surely say that it is at once a philosophy, because it puts plainly before us an explanation of the scheme of evolution of both the souls and the bodies contained, in our solar system. It is a religion in so far as, having shown us the course of ordinary evolution, it also puts before us and advises a method of shortening that course, so that by conscious effort we may progress more directly towards the goal.