- In the 14th century the epiclesis became an issue in the polemics between Greeks and Latins, because all Eastern eucharistic prayers included an invocation of the Holy Spirit while the Roman canon of the mass did not. Most modern scholars agree that there had been an epiclesis, in the original Eucharist of the early church of Rome, in addition to the other Latin eucharistic prayers. Medieval Latin theology, however, allowed for the disappearance of the epiclesis since it was believed that the consecration of bread and wine and their transubstantiation into the body and blood of Christ took place when the priest pronounced the words of institution.
- The question of the epiclesis was debated at the Council of Ferrara-Florence (1438–45), but no formal definition was made. The medieval Latin view was then endorsed by the Council of Trent (1545–63), but the liturgical reforms adopted in Roman Catholicism after the second Vatican Council (1962–65) have included the introduction of an epiclesis in the canon of the mass. This epiclesis, however, is placed before the words of institution so that the consecratory function of the latter can still be maintained.
"At the heart of the Eucharistic celebration are the bread and wine that, by the words of Christ and the invocation of the Holy Spirit, become Christ's Body and Blood" (CCC #1333).
Roman Canon (Eucharistic Prayer I)
Be pleased, O God, we pray,
to bless, acknowledge,
and approve this offering in every respect;
make it spiritual and acceptable,
so that it may become for us
the Body and Blood of Your most beloved Son,
Our Lord Jesus Christ.