The Sacrament of Marriage
The Roman Catholic Church has a deep belief in the value and purpose of marriage as seen in the following excerpts from Sacred Scripture, the Code of Canon Law and the Catechism of the Catholic Church (information on the Code of Canon Law; information on Catechism of the Catholic Church)
Marriage in the Catholic Church is sacramental; there are specific requirements for marrying. Before planning your wedding, contact your parish priest and discuss your upcoming marriage. He will assist you in completing the pre-marriage documents and in booking a marriage preparation course.
Code of Canon Law: Can. 1055 §1. The matrimonial covenant, by which a man and a woman establish between themselves a partnership of the whole of life and which is ordered by its nature to the good of the spouses and the procreation and education of offspring, has been raised by Christ the Lord to the dignity of a sacrament between the baptized.
Can. 1056 The essential properties of marriage are unity and indissolubility, which in Christian marriage obtain a special firmness by reason of the sacrament.
Can. 1059 Even if only one party is Catholic, the marriage of Catholics is governed not only by divine law but also by canon law, without prejudice to the competence of civil authority concerning the merely civil effects of the same marriage.
From the Catechism of the Catholic Church (Article 7):
1605 Holy Scripture affirms that man and woman were created for one another: "It is not good that the man should be alone."92 The woman, "flesh of his flesh," his equal, his nearest in all things, is given to him by God as a "helpmate"; she thus represents God from whom comes our help.93 "Therefore a man leaves his father and his mother and cleaves to his wife, and they become one flesh."94 The Lord himself shows that this signifies an unbreakable union of their two lives by recalling what the plan of the Creator had been "in the beginning": "So they are no longer two, but one flesh."95
1603 "The intimate community of life and love which constitutes the married state has been established by the Creator and endowed by him with its own proper laws.... God himself is the author of marriage."87 The vocation to marriage is written in the very nature of man and woman as they came from the hand of the Creator. Marriage is not a purely human institution despite the many variations it may have undergone through the centuries in different cultures, social structures, and spiritual attitudes. These differences should not cause us to forget its common and permanent characteristics. Although the dignity of this institution is not transparent everywhere with the same clarity,88 some sense of the greatness of the matrimonial union exists in all cultures. "The well-being of the individual person and of both human and Christian society is closely bound up with the healthy state of conjugal and family life."89