Reading and considering spiritual truth for those who have left this earth is an important task.
This is one of the broadest descriptions I have read.
“The so-called dead need the living, for otherwise they would only be able to behold themselves on earth, that is, their own life that has run its course. This explains the deed of love that we can perform for the dead by reading spiritually to them, not aloud, but in thoughts, by imagining the dead here with us in thought. In this way we can read to a number of dead at one and the same time, with or without a book, and thereby perform a considerable deed of love for them.
The thoughts must be related to a spiritual content, otherwise they have no meaning for the dead. These thoughts create an external world for the dead that he can perceive. To think chemical laws and so forth has no sense because these laws are meaningless in the spiritual world.
It is also impossible, as one might easily imagine, to learn any more spiritual science after death because spiritual science after all contains spiritual ideas. We can do a great service to souls who have already heard something of spiritual science by reading cycles of lectures to them. Although such souls are able to perceive a spiritual world, they are nevertheless not able to form concepts and ideas that one can only acquire here on earth.” Rudolf Steiner, Life Between Death and Rebirth lecture XVI Life After Death, May 13, 1913
Art: The Morning after the Deluge, William Turner