Mediator Dei: On the Sacred Liturgy by Pope Pius XII

English Version of The Encyclical Mediator Dei of Pope Pius XII, May 15, 1956: On the Sacred Liturgy. A reprimand to innovators. The Nature of Liturgy, especially the Mass. Eucharistic worship. Divine Office and Liturgical Year. Pastoral directives. Many novelties of the Novus Ordo are specifically condemned in this encyclical.