I. Introduction

Christianity, the most widely distributed of the world religions, having substantial representation in all the populated continents of the globe. Its total membership may exceed 1.7 billion people.
Like any system of belief and values—be it Platonism, Marxism, Freudianism, or democracy—Christianity is in many ways comprehensible only “from the inside,” to those who share the beliefs and strive to live by the values; and a description that would ignore these “inside” aspects of it would not be historically faithful. To a degree that those on the inside often fail to recognize, however, such a system of beliefs and values can also be described in a way that makes sense as well to an interested observer who does not, or even cannot, share their outlook.