writings of the fathers, as to be ignorant of the formulary used
principally of the sacraments, the initiated understand what is said:
it occurs at least fifty times in Chrysostom, and almost as frequently
in Augustine". S. Fulgentius inserts in his answer to the deacon
Ferrandus the following words of S. Augustine to the neophytes "This
which you see on the altar of God you saw last night: but what it was,
what it meant, and of what a great thing it contains the sacrament,
you have not yet heard. What therefore you see is bread and the
chalice. What your faith demands is, that the bread is the body of
Christ, and the chalice contains the blood of Christ". S. Cyril
of Jerusalem in his catechetical discourses addressed to the newly
baptised inculcates in the strongest terms the doctrine of the real
presence, but charges them most strictly not to communicate to the
catechumens his instructions. In consequence of this practice the
early fathers often speak obscurely of the B. Sacrament, and call it
bread and wine and _fermentum_ after the consecration, though they
clearly teach the _faithful_ the doctrine of the real presence[6].

[Sidenote: Liturgy of the Roman church.]

Pope Innocent I, writing to Decentius at the beginning of the fifth
century, attributes the liturgy of the Roman church to St. Peter. It
was first written in the fifth century; and Pope Vigilius sending it
in 538 to Profuturus derives it from Apostolic tradition. The most
ancient sacramentary or liturgical work extant of the Roman church is
that of Gelasius who was Pope from 492 to 496[7]. He collected prayers
composed by more ancient authors, and also composed some himself:
and this Gelasian compilation was reformed by Gregory the Great and
reduced to one volume[8], which may be considered as the prototype
of our present liturgy. The canon or most solemn part of the mass