in the Ro- man liturgy this invocation is entirely wanting, and the sanc- tification of the elements is considered as effected by the priest's rehearsal of the "Words of Institution. This has re- mained a point of dispute between the Greek and the Roman churches. Gregory the Great asserts that the apostles used nothing in the consecration but the Words of Institution and the Lord's Prayer.' But whence could he know this in the sixth century, since the 'New Testament gives us no informa- tion on the subject ? An invocatio Spiritus Sancti upon the elements is nowhere mentioned; only a thanksgiving of the Lord, preceding the Words of Institution, and forming also, it may be, an act of consecration, though neither in the sense of the Greek nor of the Roman church. The Words of Insti- tution : " This is my body," (fee, are moreover addressed not to God, but to the disciples, and express, so to speak, the re- sult of the Lord's benediction.* ' Epist. ad Joann. Episc. Sjriac. - On this disputed point Neale agrees with the Oriental church, Freeman with the Latin. Comp. Xeale, Tetralogia Liturgica, Prsefat. p. xv. sqC[., and his English edition of the Primitive Liturgies of S. Mark, S. James, etc., p. 23. In the latter place he says of the iwiK\ricrts Uviv/xaTos ayiov: "By the Livocation of the Holy Ghost, according to the doctrine of the Eastern church, and not by the words of in- stitution, the bread and wine are ' changed,' ' transmuted,' ' transelemented,' ' tran- substantiated ' into our Lord's Body and Blood. This has always been a point of contention between the two churches — the time at which the change takes place. Originally, there is no doubt that the Invocation of the Holt Ghost formed a part of all liturgies. The Petrine has entirely lost it : the Ephesine (GaUican and Moz- arabic) more or less retains it : as do also those mixtures of the Ephesine and Pe- trine— the Ambrosian and Patriarchine or Aquileian. To use the words of the authorized Russian Catechism : ' Why is this (the Invocation) so essential ? Because at the moment of this act, the bread and wine are changed or transubstantiated into the very Body of Christ and into the very Blood of Christ. How are we to imder- stand the word Transubstantiation ? In the exposition of the faith by the Eastern Patriarchs, it is said that the word is not to be taken to define the manner in which the bread and wine are changed into the Body and Blood of our Lord ; for this 524 THIRD PERIOD. A.D. 311-590. 8. The Oriental liturgy allowed, more like the Protestant church, the use of the various vernaculars, Greek, Syriac, Aiinenian, Coptic, &c. ; while the Roman mass, in its desire for uniformity, sacrijBces all vernacular tongues to the Latin, and 60 makes itself unintelligible to the people. 4. The Oriental liturgy is, so