It must be stated that nourishment after death can be drawn only from the ideas and thoughts of those with whom there was some connection during life; nourishment cannot be drawn from those with whom there was no connection at all. When we cultivate Anthroposophy today in order that there may again be in souls a spirituality which can be nourishment for the dead, we are not working only for the living, or merely in order to provide them with some kind of theoretical satisfaction, but we try to fill our hearts and souls with thoughts of the spiritual world because we know that the dead who were connected with us on earth must draw their nourishment from these thoughts. We feel ourselves to be workers not only for living human beings, but workers too in the sense that anthroposophical activity, the spread of anthroposophical life, is also of service to the spiritual worlds. In speaking to the living for their life by day, we promote ideas which, bringing satisfaction as they do in the life by night, are fruitful nourishment for the souls whose karma it was to die before us. And so we feel the urge not only to spread Anthroposophy by the ordinary means of communication, but deep down within us there is the longing to cultivate Anthroposophy in communities, in groups, because this is of real value.
As I have said, the dead can draw nourishment only from souls with whom they were associated in life. We therefore try to bring souls together in order that the harvest-fields for the dead may become more and more extensive. Many a human being who after death finds no harvest-field because all his family are materialists, finds it among the souls of anthroposophists with whom he had had some connection. That is the deeper reason for working together in community, and why we are anxious that the dead should have been able before death to know anthroposophists who are still occupied on the earth with spiritual things; for when these people are asleep the dead can draw nourishment from them.
Source: Rudolf Steiner – GA 140 – 1. LINKS BETWEEN THE LIVING AND THE DEAD – Bergen, October 10,1913