Catechism of the Catholic Church
1655 Christ chose to be born and grow up in the bosom of the holy family of Joseph and Mary. The Church is nothing other than "the family of God." From the beginning, the core of the Church was often constituted by those who had become believers "together with all [their] household." 166 When they were converted, they desired that "their whole household" should also be saved. 167 These families who became believers were islands of Christian life in an unbelieving world.
1656 In our own time, in a world often alien and even hostile to faith, believing families are of primary importance as centers of living, radiant faith. For this reason the Second Vatican Council, using an ancient expression, calls the family the Ecclesia domestica. 168 It is in the bosom of the family that parents are "by word and example . . . the first heralds of the faith with regard to their children. They should encourage them in the vocation which is proper to each child, fostering with special care any religious vocation." 169
1657 It is here that the father of the family, the mother, children, and all members of the family exercise the priesthood of the baptized in a privileged way "by the reception of the sacraments, prayer and thanksgiving, the witness of a holy life, and self-denial and active charity." 170 Thus the home is the first school of Christian life and "a school for human enrichment." 171 Here one learns endurance and the joy of work, fraternal love, generous—even repeated—forgiveness, and above all divine worship in prayer and the offering of one's life.
1658 We must also remember the great number of single persons who, because of the particular circumstances in which they have to live—often not of their choosing—are especially close to Jesus' heart and therefore deserve the special affection and active solicitude of the Church, especially of pastors. Many remain without a human family often due to conditions of poverty. Some live their situation in the spirit of the Beatitudes, serving God and neighbor in exemplary fashion. The doors of homes, the "domestic churches," and of the great family which is the Church must be open to all of them. "No one is without a family in this world: the Church is a home and family for everyone, especially those who 'labor and are heavy laden.'" 172
1659 St. Paul said: "Husbands, love your wives, as Christ loved the Church.... This is a great mystery, and I mean in reference to Christ and the Church" (Eph 5:25, 32).
1660 The marriage covenant, by which a man and a woman form with each other an intimate communion of life and love, has been founded and endowed with its own special laws by the Creator. By its very nature it is ordered to the good of the couple, as well as to the generation and education of children. Christ the Lord raised marriage between the baptized to the dignity of a sacrament (cf. CIC, can. 1055 § 1; cf. GS 48 § 1).
1661 The sacrament of Matrimony signifies the union of Christ and the Church. It gives spouses the grace to love each other with the love with which Christ has loved his Church; the grace of the sacrament thus perfects the human love of the spouses, strengthens their indissoluble unity, and sanctifies them on the way to eternal life (cf. Council of Trent: DS 1799).
1662 Marriage is based on the consent of the contracting parties, that is, on their will to give themselves, each to the other, mutually and definitively, in order to live a covenant of faithful and fruitful love.
1663 Since marriage establishes the couple in a public state of life in the Church, it is fitting that its celebration be public, in the framework of a liturgical celebration, before the priest (or a witness authorized by the Church), the witnesses, and the assembly of the faithful.
1664 Unity, indissolubility, and openness to fertility are essential to marriage. Polygamy is incompatible with the unity of marriage; divorce separates what God has joined together; the refusal of fertility turns married life away from its "supreme gift," the child (GS 50 § 1).
1665 The remarriage of persons divorced from a living, lawful spouse contravenes the plan and law of God as taught by Christ. They are not separated from the Church, but they cannot receive Eucharistic communion. They will lead Christian lives especially by educating their children in the faith.
1666 The Christian home is the place where children receive the first proclamation of the faith. For this reason the family home is rightly called "the domestic church," a community of grace and prayer, a school of human virtues and of Christian charity.
English Translation of the Cathechism of the Catholic Church for the United States of America © 1997, United States Catholic Conference, Inc.