Some spiritual movements want to divert the human being from the external world; one should look for the higher self only in oneself. This point of view can never lead to a real knowledge; it is unchristian and antichristian at the same time. Only in the orientation to the world, which surrounds us, we find our higher self. We must seek for the god in the invisible worlds and in all external creatures, facts, and processes. If anybody says to us, deny the external world, this external matter does not exist, he denies the divine world; and there is for a big perspective no worse knowledge than turning away from the outside world. Just the deepening in the outside world leads to higher knowledge. Everything physical dries out, if it is raised a little above the earth, everything mental dries out, if it is raised a little above the spiritual world.
Source: Rudolf Steiner – GA 54 – The Riddles of the World and Anthroposophy: Inner Development – Berlin, 19th April 1906