The Vocation of Marriage
God, who created man out of love, also calls him to love—the fundamental and innate vocation of every human being. For man is created in the image and likeness of God who is himself love. Since God created him man and woman, their mutual love becomes an image of the absolute and unfailing love with which God loves man. It is good, very good, in the Creator’s eyes. And this love which God blesses is intended to be fruitful and to be realized in the common work of watching over creation: “And God blessed them, and God said to them: ‘Be fruitful and multiply, and fill the earth and subdue it.’ ” (Catechism of the Catholic Church #1604)
God, who created man out of love, also calls him to love. God is love. Before anything or anyone was created, Father, Son, and Spirit lived in a fully-absorbing, full-satisfying relationship of love with each other. Desiring to have others who could know the awesomeness of that love, God created angels, humans, and other creatures. We were created with the capacity to love in the image of the love between Father, Son, and Spirit.
... to love—the fundamental and innate vocation of every human being. Vocation is the way that God beckons us to live our fullest life. Though we have different individual vocations, all vocations are given to us by God to embrace love... to be loved, and to love in return.
For man is created in the image and likeness of God who is himself love. One of the key ways that men and women are made in the image and likeness of God is that we can experience love, both receiving and giving. Lesser creatures, such as animals, also can experience love in a lesser way, but we are most like God, meaning that our love is more potent and powerful, and that we can appreciate what it means to love.
Since God created him man and woman, their mutual love becomes an image of the absolute and unfailing love with which God loves man. God the Father loves the God the Son fully, and God the Son loves God the Father fully. Likewise, God the Father loves God the Holy Spirit fully, and God the Holy Spirit loves God the Father fully. The same goes for God the Son and God the Holy Spirit. The truest and fullest love encompasses the entirety on one's being for another. Father, Son, and Spirit each also love human beings with His whole self. We, as men and women, are able to reflect the totality of giving of oneself in love to each other that the Divine Persons live.
It is good, very good, in the Creator’s eyes. Reflecting the love of the Creator is exactly what He created us for!
And this love which God blesses is intended to be fruitful and to be realized in the common work of watching over creation: “And God blessed them, and God said to them: ‘Be fruitful and multiply, and fill the earth and subdue it.’ ” God's love resulted in creation and caring for creation. Our love, imaging God's love, is also meant to result in creation and caring for that creation. Bringing children into this world, and providing for them, is among the most God-like activities that we can do.
Holy Scripture affirms that man and woman were created for one another: “It is not good that the man should be alone.” 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. “Therefore a man leaves his father and his mother and cleaves to his wife, and they become one flesh.” 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.” (Catechism of the Catholic Church #1605)
Self-gift & Sacrament
When a man and a woman join together in Holy Matrimony, they express the gift of their whole selves to each other. This self-gift is the highest image of the self-gift of Father, Son, and Spirit in the Holy Trinity. Such a self-gift must be faithful, fruitful, and entire to reflect the perfect love of the Divine Persons. And in giving oneself fully to one's spouse, husband and wife join in an indissoluble union, becoming one flesh.
Jesus elevated marriage to the level of sacrament, such that, as in all the sacraments, God pours out His sanctifying grace through it. Christians who are united in Holy Matrimony become a channel of God's grace into the world. This grace sanctifies husband and wife and binds them more closely together, overflows into their children and communities, and provides a witness for others to see the face of the Lord in the couple's experiences of spousal love. And, just as no other sacrament can be "undone" by subsequent actions, nothing can break the sacred bond of matrimony until the death of one of the spouses.
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. 1055, Code of Canon Law)
The vocation of marriage has two primary goals: (1) the mutual enrichment and flourishing of husband and wife, and (2) the bearing and raising of children.
Husband and wife promise to be faithful to each other, to love each other, and to honor each other all the days of one's life. Spouses should remember this pledge every day of their life. Their promise to each other is realized in making the other's good their first prirority in life. And as the greatest good is the attainment of the Beatific vision, a married person's very first goal should always be to help the other attain holiness and Heaven.
Husband and wife also promise to be open to children. Such openness is not accidental to marriage, but must be a direct part of the intention to enter into the vocation of marriage. A valid marriage without children is possible, as long as both parties are indeed ready to welcome children that God may send to them. But if two people come together without an openness to bringing new life into the world, they cannot enter a valid marriage, but only a pale and poor imitation. To mirror God's creative love, husband and wife must be willing to give of themselves to contribute to the created world by welcoming new life into it.