Under the title of "who belongs to the Catholic Church?", the new Catechism notes that fullness of Catholic communion depends on maintaining "the bonds constituted by the profession of faith, the sacraments, ecclesiastical government, and communion" (no. 836).
The Second Vatican Council was aimed at formulating principles for the renewal of ecclesial life in all its aspects. More than thirty years later, varying evaluations of the results are made. Some persons, perhaps feeling that renewal was a dangerous idea in itself, hold that in any case it went off the tracks from the start. Others think that it ran into too much entrenched opposition from conservative forces, and is now largely dead-ended, an ideal or a dream they no longer really believe in. For others again, it remains a program of hope, which is still being attempted or needs to be attempted. Pope John Paul II is evidently one of these; he is a firm believer in renewal and, as I see his ministry, it is being constantly spent in seeking to bring it about.
Christ, present in his Church, continues to proclaim the message of Redemption and to offer the means of salvation to generation after generation: "I am with you always, to the close of the age" (Mt 28:20). He sent his Apostles and their successors to teach, guide and sanctify in his name, promising that he would be behind their teaching ("he who hears you hears me, and he who rejects you rejects me" (Lk 10:16), and guaranteeing those who obeyed their authority that it had a divine seal of approval placed on it: "whatever you [plural] bind on earth shall be bound in heaven, and whatever you [plural] loose on earth shall be loosed in heaven" (Mt 18:18).
Salvation comes from Jesus Christ who alone has the words of eternal life (cf. Jn 6:68). Hence arises the vital need to accept his Revelation; "he who believes and is baptized will be saved; but he does not believe will be condemned" (Mk 16:15-16).
The truth that saves is something given; it is not invented by us, but revealed by God. It has already in fact been given in its entirety, and so the Church teaches that there can be no new public revelation after the death of the last Apostle (Denz. 3421).