The union of a man and a woman is natural. The natural language of the human body is such that the man gives to the woman and the woman receives the man. The love and friendship between a man and a woman grow into a desire for marriage. The Sacrament of marriage gives the couple the grace to grow into a union of heart and soul, to provide stability for themselves and their children. Children are the fruit and bond of a marriage.
The bond of marriage between a man and a woman lasts all the days of their lives, and the form of the rite consists of the mutual exchange of vows by a couple, both of whom have been baptized. The priest or deacon serves as a witness to this sacred Sacrament in the Roman rite; with the couple serving as ministers of the Sacrament itself. The matter follows later through consummation of the marriage act.
Sacred Scripture begins with the creation of man and woman in the image and likeness of God, and concludes with a vision of the "wedding-feast of the Lamb (Revelations 19:7, 9)". The bond of marriage is compared to God's undying love for Israel in the Old Testament, and Christ's love for His Church in the New Testament.
Jesus stresses the importance of the marriage bond in His Ministry (Matthew 19:6, 8). The importance of marriage is substantiated by the presence of Christ at the wedding feast of Cana, where He began His public ministry at the request of His mother Mary by performing His first miracle (John 2). It is the Apostle Paul who identifies the marriage of man and woman with the unity of Christ and His Church.