The topic of
communicatio in sacris is confusing because participation and sacraments are interrelated. The Holy Eucharist is the focus of the Mass or Divine Liturgy. So ecumenical participation is not to compete with the usual Sunday and Holy Day celebration, so you can receive the Holy Mysteries and not express indifference which would lead some to think that non-Catholic Churches may have the fullness of the faith.
This exerpt shows how the norms are applied.
http://www.vatican.va/img/vuoto.gifPontifical Council for the Pastoral Care of Migrants and Itinerant People
***People on the Move ***
N° 105 (Suppl.), December 2007
Ecumenical cooperation and communicatio in sacris
“From the standpoint of the norms regarding *communicatio in sacris *it seems clear that the guidelines contained in the
Ecumenical Directory have reached
the limits of the what is permitted by theology. Bishops and priests should be familiar with the norms of the *Ecumenical Directory. *The analysis of local situations is the task of the diocesan bishop (and of the Bishops’ Conference) for their respective territories, whereas the
discernment of individual personal cases is the task of the ministers who celebrate the sacraments, on the basis of the pastoral instructions of the local bishop.”
You see the Vatican II instruction expressed in (1964)
Unitatis Redintegratio
vatican.va/archive/hist_councils/ii_vatican_council/documents/vat-ii_decree_19641121_unitatis-redintegratio_en.html
- Common participation in worship (communicatio in sacris) which harms the unity of the Church or involves formal acceptance of error or the danger of aberration in the faith, of scandal and indifferentism, is forbidden by divine law.(32) On the other hand, pastoral experience shows clearly that, as regards our Eastern brethren, there should be taken into consideration the different cases of individuals, where neither the unity of the Church is hurt nor are verified the dangers that must be avoided, but where the needs of the salvation of souls and their spiritual good are impelling motives. For that reason the Catholic Church has always adopted and now adopts rather a mild policy, offering to all the means of salvation and an example of charity among Christians, through participation in the sacraments and in other sacred functions and things. With this in mind, “lest because of the harshness of our judgment we be an obstacle to those seeking salvation” (31) and in order more and more to promote union with the Eastern Churches separated from us, the Sacred Council lays down the following policy.
- Without prejudice to the principles noted earlier, Eastern Christians who are in fact separated in good faith from the Catholic Church, if they ask of their own accord and have the right dispositions, may be admitted to the sacraments of Penance, the Eucharist and the Anointing of the Sick. Further, Catholics may ask for these same sacraments from those non-Catholic ministers whose churches possess valid sacraments, as often as necessity or a genuine spiritual benefit recommends such a course and access to a Catholic priest is physically or morally impossible.(33)
- Further, given the same principles, common participation by Catholics with their Eastern separated brethren in sacred functions, things and places is allowed for a just cause.(34)
- This conciliatory policy with regard to “communicatio in sacris” (participation in things sacred) with the brethren of the separated Eastern Churches is put into the care and control of the local hierarchs, in order that, by combined counsel among themselves and, if need be, after consultation also with the hierarchs of the separated churches, they may by timely and effective regulations and norms direct the relations among Christians.
