298 The Faith of Our Fathers Most High God."401 Tradition, with its hundred tongues, proclaims the perpetual oblation of the Sacrifice of the Mass, from the time of the Apostles to our own days. If we consult the Fathers of the Church, who have stood like faithful sentinels on the watch-towers of Israel, guarding with a jealous eye the deposit of faith, and who have [314] been the faithful witnesses of their own times and the recorders of the past; if we consult the General Councils, at which were assembled the venerable hierarchy of Christendom, they will all tell us, with one voice, that the Sacrifice of the Mass is the centre of their religion and the acknowledged institution of Jesus Christ. Another remarkable evidence in favor of the Divine institution of the Mass is furnished by the Nestorians and Eutychians, who separated from the Catholic Church in the fifth century, and who still exist in Persia and in other parts of the East, as well as by the Greek schismatics, who severed their connection with the Church in the ninth century. All these sects, as well as the numerous others scattered over the East, retain to this day the oblation of the Mass in their daily service. As these Christian communities have had no communication with the Catholic Church since the period of their separation from her, they could not, of course, have borrowed from her the doctrine of the Eucharistic Sacrifice; consequently they must have received it from the same source from which the Church derived it, viz., from the Apostles themselves. But of all proofs in favor of the Apostolic origin of the Sacrifice of the Mass, the most striking and the most convincing is found in the Liturgies of the Church. The Liturgy is the established Ritual of the Church. It is the collection of the authorized prayers of divine worship. These prayers are fixed and immovable. Among others we have the Liturgy of Jerusalem, ascribed to the Apostle St. James; the Liturgy of Alexandria, attributed to St. Mark