Catechism of the Catholic Church
a, c, d, and e. Para. 1626: The Church holds the exchange of consent between the spouses to be the indispensable element that "makes the marriage" (CIC, can. 1057 § 1). If consent is lacking there is no marriage.
Para. 1630: The priest (or deacon) who assists at the celebration of a marriage receives the consent of the spouses in the name of the Church and gives the blessing of the Church. The presence of the Church's minister (and also of the witnesses) visibly expresses the fact that marriage is an ecclesial reality.
Para. 1631: This is the reason why the Church normally requires that the faithful contract marriage according to the ecclesiastical form. Several reasons converge to explain this requirement (Cf. Council of Trent: DS 1813-1816; CIC, can. 1108):
- Sacramental marriage is a liturgical act. It is therefore appropriate that it should be celebrated in the public liturgy of the Church;
- Marriage introduces one into an ecclesial order, and creates rights and duties in the Church between the spouses and towards their children;
- Since marriage is a state of life in the Church, certainty about it is necessary (hence the obligation to have witnesses);
- The public character of the consent protects the "I do" once given and helps the spouses remain faithful to it.