Communicatio in Sacris and Shared Worship

Communicatio in sacris literally denotes sharing in sacred things and has been used with different breadth in canonical and theological sources. Common prayer, attendance at worship, use of sacred places, sacramental sharing, sponsorship, concelebration, and reception of Holy Communion do not all receive one rule. The governing text, sacrament, minister, recipient, Church or Ecclesial Community, necessity, and danger of indifferentism must be identified before declaring an act permitted or forbidden.

Unitatis redintegratio gives two principles held together: worship manifests the Church's unity, which ordinarily limits common worship, and sacramental life communicates grace, which can commend sharing in defined circumstances. Ecumenism neither treats sacraments as private hospitality nor withholds grace to dramatize separation. Ecclesial Communion is real but imperfect among validly baptized Christians, and the Church disciplines sacred sharing in accordance with the degree and form of communion actually present.^[1]

Catholic ministers may administer Penance, Eucharist, and Anointing to members of Eastern Churches not in Full Communion, and to members of other Churches judged by the Apostolic See to be in the same sacramental condition, when they ask on their own and are properly disposed. Their valid priesthood and Eucharist explain this discipline. It does not authorize proselytism, disregard the other Church's discipline, or erase the wound of separation.

For other baptized Christians, danger of death or another grave necessity judged by the diocesan bishop or conference is required, along with inability to approach their own minister, spontaneous request, proper disposition, and manifestation of Catholic faith in the sacrament. Anglican or Protestant identity alone does not satisfy those conditions. Eucharistic Sharing remains ordered to full ecclesial communion even when pastoral necessity permits an exceptional sacramental act.

The diocesan bishop, conference of bishops, Holy See, and competent Eastern authorities have roles defined by universal and particular law. General local norms require consultation where canon 844 provides it, and individual ministers must apply rather than expand them. Eucharistic concelebration between Catholic priests and ministers of communities not in full communion is forbidden because concelebration itself manifests a unity in priesthood, sacrifice, and governance that does not yet exist.

Pastoral decisions should be discreet, truthful, and free from both rigorist display and casual indifferentism. A public service may require advance explanation to families, ministers, and congregations; a private emergency may call for swift judgment. The Ecumenical Vademecum presents sacred sharing as genuine care for souls governed by ecclesiology. Its goal is grace and unity in truth, never a symbolic performance that turns the Eucharist into a negotiating instrument.^[3]