30. The Catholic Church's teaching on the relationship between priestly ministry and the Eucharist and her teaching on the Eucharistic Sacrifice have both been the subject in recent decades of a fruitful dialogue in the area of ecumenism. We must give thanks to the Blessed Trinity for the significant progress and convergence achieved in this regard, which lead us to hope one day for a full sharing of faith. Nonetheless, the observations of the Council concerning the Ecclesial Communities which arose in the West from the sixteenth century onwards and are separated from the Catholic Church remain fully pertinent: “The Ecclesial Communities separated from us lack that fullness of unity with us which should flow from Baptism, and we believe that especially because of the lack of the sacrament of Orders they have not preserved the genuine and total reality of the Eucharistic mystery. Nevertheless, when they commemorate the Lord's death and resurrection in the Holy Supper, they profess that it signifies life in communion with Christ and they await his coming in glory”.62
The Catholic faithful, therefore, while respecting the religious convictions of these separated brethren, must refrain from receiving the communion distributed in their celebrations, so as not to condone an ambiguity about the nature of the Eucharist and, consequently, to fail in their duty to bear clear witness to the truth. This would result in slowing the progress being made towards full visible unity. Similarly, it is unthinkable to substitute for Sunday Mass ecumenical celebrations of the word or services of common prayer with Christians from the aforementioned Ecclesial Communities, or even participation in their own liturgical services. Such celebrations and services, however praiseworthy in certain situations, prepare for the goal of full communion, including Eucharistic communion, but they cannot replace it.
The fact that the power of consecrating the Eucharist has been entrusted only to Bishops and priests does not represent any kind of belittlement of the rest of the People of God, for in the communion of the one body of Christ which is the Church this gift redounds to the benefit of all.