The word Canon means a rule or norm and it was used at quite an early stage of the Church's history to denote both general principles governing the life of the Christian society and particular enactments of Christian assemblies. The subject matter of the canons is as wide as the life of the Church itself and consequently very varied in its nature. At one end of its range it is concerned with matters fundamental to the Church's existence such as the creeds and sacraments. At the other it deals with practical arrangements such as the ownership and use of buildings. At a recent conference with German Lutherans I was asked whether the canon law was jus divinum or jus humanum, and I felt bound to reply. ‘Both’, because of this wide range which stretches from revelation to convenience.