Four Marks of the Church
"This is the sole Church of Christ, which in the Creed we profess to be one, holy, catholic and apostolic." These four characteristics, inseparably linked with each other,indicate essential features of the Church and her mission. The Church does not possess them of herself; it is Christ who, through the Holy Spirit, makes his Church one, holy, catholic, and apostolic, and it is he who calls her to realize each of these qualities.
The Church Is One
"The Church is one: she acknowledges one Lord, confesses one faith, is born of one Baptism, forms only one Body, is given life by one Spirit, for the sake of one hope, at whose fulfillment all divisions will be overcome."
The Church Is Holy
The Church is holy: the Most Holy God is her author; Christ, her bridegroom, gave himself up to make her holy; the Spirit of holiness gives her life. Since she still includes sinners, she is "the sinless one made up of sinners". Her holiness shines in the saints; in Mary she is already all-holy."
The Church Is Catholic
"The Church is catholic: she proclaims the fulness of the faith. She bears in herself and administers the totality of the means of salvation. She is sent out to all peoples. She speaks to all men. She encompasses all times. She is "missionary by her very nature".
The Church Is Apostolic
"The Church is apostolic. She is built on a lasting foundation: "the twelve apostles of the Lamb". She is indestructible. She is upheld infallibly in the truth: Christ governs her through Peter and the other apostles, who are present in their successors, the Pope and the college of bishops.
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