We are born and die alone, and are often alone in between. But this is true of all human beings, in their millions. So in another sense we are not alone at all, quite the opposite. To manage other shared problems our species has devised organisms specific to each. The organisms specific to our shared solitudes are religions. Because of the paradox in which they originate, religions have a double character: private and public. There is no clearer example than Christianity. It could never have come into existence without some degree of organization, with its half-dozen early members or, thanks to development of Roman and Jewish traditions, millions. But the whole purpose of the organization was to cultivate, in each member, responses essentially private, known only to God. The public and private elements in Christianity are always in tension, usually a creative one; but sometimes not. Murrays five essays, produced for various occasions, consider different aspects of this tension, creative or otherwise, in the western church between, approximately, the millennium and 1300.