Christian marriage is a free, lifelong and natural union between a man and a woman. Christ has “raised marriage to a sacrament” (CCC 1660). In it, he is present in a particularly powerful way as the couple express their consent to each other. The sacrament has become a “living sign” of the union between Christ and his Church (cfr Ephesians 5,21-33). Just as Christ is united to the Church, so, through their consent, are a couple united in a permanent and exclusive way to one another.