Why Call Them Back from Heaven — Clifford D. Simak

A corporation promising immortality hides a sinister secret in this “extremely provocative” sci-fi novel (Judith Merril, author and editor).
 
Since the dawn of mankind, immortality has been the ultimate reward. But by the year 2148, it requires no act of faith to believe in an afterlife. Forever Center promises to bring people back to a life beyond death. Now everyone spends their lives in poverty, giving all their money to Forever Center to ensure their happiness and comfort in the next eternal life.
 
Daniel Frost is a key man at Forever Center, but when he accidentally stumbles onto some classified documents, Dan incurs the wrath of an unseen enemy and is framed for a terrible crime. Now, his right to immortality has been revoked and he is a social outcast, condemned to the desperate life of a hunted animal. As a renegade lawyer and a brilliant mathematician attempt to help him, they reveal some shattering information about Forever Center . . . and the essence of life itself.