Success with interreligious dialogue and with interreligious mission depends upon an agreed upon definition of “religion.” We must not define “religion” in such a way that Christianity is a religion and Buddhism is not. Therefore, belief in a Person-like Supreme Being cannot be our definition of religion. Let me suggest, therefore, the following definition of religion:
Religion is a temporal, humanly-created, down-to-Earth practice that points beyond itself in expression of an ultimate devotion to that which is Ultimate.
This definition requires understanding what we mean by “Ultimate,” but first a few examples of practices that are an expression of an ultimate devotion to that which is not ultimate. Nationalism is an example of an ultimate devotion to a nation, a reality that is not ultimate. Similarly, humanism is an example of an ultimate devotion to the human, a reality that is not ultimate. Communism is an example of an ultimate devotion to a theory of economic history—again an ultimate devotion to something not ultimate. These three widespread devotions might be called quasi-religions, for what they do takes the place of religion, if religion is defined as an ultimate devotion to that which is Ultimate.