CCC 1630
Christian Mystery›SECTION TWO THE SEVEN SACRAMENTS OF THE CHURCH›CHAPTER THREE THE SACRAMENTS AT THE SERVICE OF COMMUNION›III. Matrimonial Consent
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.