You must remind yourselves that as well as living through his life here between birth and death, man passes again and again through the life between death and a new birth. Just as here on earth we have experiences through the instrumentality of our body, we also have experiences between death and a new birth, and these experiences are by no means without significance for what we do during our earthly existence in the physical body. But neither are they without significance for what happens on earth as a whole.
For only part — and indeed the rather lesser part — of what happens on the earth originates from those who are living in the physical body. The dead are perpetually working into our physical world. The forces of which man is unwilling to speak to-day in the age of materialism are nevertheless at work in the physical world. Our physical environment is fashioned and permeated not only by the forces emanating from the spiritual world, from the Beings of the higher Hierarchies, but forces proceeding from the dead also penetrate into what surrounds and overtakes us here. So that a full and complete survey of man’s life is possible only if we look beyond what can be told us by knowledge obtained through the senses and through history, here on earth.
Source: Rudolf Steiner – GA 196 – Some Conditions for Understanding Supersensible Experiences – Dornach, 18th January 1920