""The one great and telling charge made against Christian religion in the modern period,"" writes Amos Wilder, ""is that it is otherworldly, escapist and irrelevant to the problems of life."" There is a good deal of truth in this charge, Dr. Wilder feels--whether we look at Catholicism or Protestantism, orthodoxy or liberalism. Christianity, in one way or another, has given the impression of being mainly concerned with the next world or with private...