1. The Oneness of Christ's Church

1One is the Church, which after His Resurrection our Savior handed over to Peter as Shepherd (cf. Jn 21:17), commissioning him and the other apostles to propagate and govern her (cf. Mt 18:18ff.) (and which) He erected for all ages as "the pillar and mainstay of the truth" (cf. 1 Tm 3:15) And this Church of Christ, "constituted and organized in this world as a society, subsists in the Catholic Church, which is governed by the Successor of Peter and the bishops in union with that Successor."(3) This declaration of the Second Vatican Council is illustrated by the same Council's statement that "it is through Christ's Catholic Church alone, which is the general means of salvation, that the fullness of the means of salvation can be obtained,"(4) and that same Catholic Church "has been endowed with all divinely revealed truth and with all the means of grace"(5) with which Christ wished to enhance His messianic community. This is no obstacle to the fact that during her early pilgrimage the Church, "embracing sinners in her bosom, is at the same time holy and always in need of being purified,"(6) nor to the fact that "outside her visible structure," namely in Churches and ecclesial communities which are joined to the Catholic Church by an imperfect communion, there are to be found "many elements of sanctification and truth (which), as gifts properly belonging to the Church of Christ, possess an inner dynamism towards Catholic unity."(7) For these reasons, "Catholics must joyfully acknowledge and esteem truly Christian endowments derived from our common heritage, which are to be found among our separated brethren,"(8) and they must strive for the re-establishment of unity among all Christians, by making a common effort of purification and renewal,(9) so that the will of Christ may be fulfilled and the division of Christians may cease to be an obstacle to the proclamation of the Gospel throughout the world.(10) But at the same time Catholics are bound to profess that through the gift of God's mercy they belong to that Church which Christ founded and which is governed by the successors of Peter and the other Apostles, who are the depositories of the original Apostolic tradition, living and intact, which is the permanent heritage of doctrine and holiness of that same Church.(11) The followers of Christ are therefore not permitted to imagine that Christ's Church is nothing more than a collection (divided, but still possessing a certain unity) of Churches and ecclesial communities. Nor are they free to hold that Christ's Church nowhere really exists today and that it is to be considered only as an end which all Churches and ecclesial communities must strive to reach.