steve-b:
Here is part of the document you linked to:
" The expression has
been used often by John Paul II in numerous addresses and documents; the principal ones, in chronological order, are the following.
In the Encyclical
Slavorum Apostoli : «For us they [Cyril and Methodius] are the champions and also the patrons of the ecumenical endeavour of the sister Churches of East and West, for
the rediscovery through prayer and dialogue
of visible unity in perfect and total communion.»
[4]
In a Letter from 1991 to the Bishops of Europe: «
Hence, with these Churches [the Orthodox Churches] relations are to be fostered as between sister Churches, to use the expression of Pope Paul VI in his Brief to the Patriarch of Constantinople, Athenagoras I.»
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In the Encyclical
Ut unum sint, the theme is developed above all in number 56 which begins in this way: «Following the Second Vatican Council and in the light of earlier tradition, it has again become usual to refer to the particular or local Churches gathered around their Bishop as “sister Churches.” In addition, the lifting of the mutual excommunications, by eliminating a painful canonical and psychological obstacle, was a very significant step on the way toward full communion.» This section concludes by expressing the wish that
the «traditional designation of “sister Churches” should ever accompany us along this path.» The topic is taken up again in number 60 of the Encyclical: «More recently, the joint international commission took a significant step forward with regard to the very sensitive question of the method to be followed in re-establishing full communion between the Catholic Church and the Orthodox Church, an issue which has frequently embittered relations between Catholics and Orthodox. The commission has laid the doctrinal foundations for a positive solution to this problem on the basis of the doctrine of sister Churches.»
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