CATECHISM OF THE CATHOLIC CHURCH
SECOND EDITION

Paragraphs 822–826

822 Concern for achieving unity "involves the whole Church, faithful and clergy alike." But we must realize "that this holy objective - the reconciliation of all Christians in the unity of the one and only Church of Christ - transcends human powers and gifts." That is why we place all our hope "in the prayer of Christ for the Church, in the love of the Father for us, and in the power of the Holy Spirit."
823 "The Church . . . is held, as a matter of faith, to be unfailingly holy. This is because Christ, the Son of God, who with the Father and the Spirit is hailed as 'alone holy,' loved the Church as his Bride, giving himself up for her so as to sanctify her; he joined her to himself as his body and endowed her with the gift of the Holy Spirit for the glory of God." The Church, then, is "the holy People of God," and her members are called "saints."
824 United with Christ, the Church is sanctified by him; through him and with him she becomes sanctifying. "All the activities of the Church are directed, as toward their end, to the sanctification of men in Christ and the glorification of God." It is in the Church that "the fullness of the means of salvation" has been deposited. It is in her that "by the grace of God we acquire holiness."
825 "The Church on earth is endowed already with a sanctity that is real though imperfect." In her members perfect holiness is something yet to be acquired: "Strengthened by so many and such great means of salvation, all the faithful, whatever their condition or state - though each in his own way - are called by the Lord to that perfection of sanctity by which the Father himself is perfect."
826 Charity is the soul of the holiness to which all are called: it "governs, shapes, and perfects all the means of sanctification."

If the Church was a body composed of different members, it couldn't lack the noblest of all; it must have a Heart, and a Heart BURNING WITH LOVE. And I realized that this love alone was the true motive force which enabled the other members of the Church to act; if it ceased to function, the Apostles would forget to preach the gospel, the Martyrs would refuse to shed their blood. LOVE, IN FACT, IS THE VOCATION WHICH INCLUDES ALL OTHERS; IT'S A UNIVERSE OF ITS OWN, COMPRISING ALL TIME AND SPACE - IT'S ETERNAL!