By the liturgy we understand not only the official prayer of the Church expressing her spiritual life, but a prayer which expresses her doctrine. In this way the liturgy is part of the apostolic mission of the Church. Thus it is not only the way the faithful may express themselves in prayer but is their birthright by reason of their baptism. The liturgy expresses the vitality of the Church and is an implementation of her mission to go and teach all nations. It has doctrinal value not only for the faithful out also for those who may be looking on from afar. It is a matter of urgency, therefore, that this educative value should be kept vital and inspiring; that its symbolism should always teach and not become a piece of mere play-acting, still less a soulless repetition by heart of some dead formula.