1. Marriage in General

Marriage (OSV Encyc. 1997)
Life is about getting to know and love God. Our starting point to know him is creation, particularly the masterpiece of visible creation: the human race. Each individual human, male or female, is made in the likeness of God. Man and woman each "images" God, in a different though complementary way. Considered together in their complementarity, they give a fuller image.
Although there is no sexuality in God, his creation of man as a sexually diversified being, also gives a key to what God is. An understanding of what it means to be masculine or feminine is essential in order to learn from a major revelation of himself inscribed by God into creation.
The encounter of what is masculine and what is feminine is an experience which everyone needs. Properly experienced and lived, it involves a deep enrichment for the human person. The experience however does not always enrich because it involves a challenge which may not be lived up to: a challenge of understanding and of attitude expressed in multiple relations, both in the family (brothers to sisters and vice-versa; father to daughter, mother to son, and vice-versa), as well as outside: boys to girls, men to women. The person who fails to arrive at (or is deprived of) an appreciation of the typical qualities of the other sex, will have a defective idea of humanity.
In a society where sexual differences are considered to be of an exclusively corporal nature, sexuality has become impoverished and no longer helps people to grow: in knowledge of humanity, or in knowledge of God.
Sexuality has its impact on major aspects of human life and growth. Social relations need the presence of masculinity and femininity, in their complementary differences. A unisex society (which eventually becomes a society bereft of any true human sexuality) is a place where people's growth in humanity is severely handicapped.
If there are many different types of sexually-characterized relationships in society and each type is important, one stands out above all as unique in God's plan: the conjugal sexual relationship. In other words, the life-long exclusive and open-to-life union between a man and a woman which is marriage.
Marital consent
"The vocation to marriage is written in the very nature of man and woman as they came from the hand of the Creator" (CCC 1603). But there must be a personal response to this vocation, as to any other. Marriage in fact begins with an act of commitment - marital consent - "by which a man and a woman, through an irrevocable covenant, mutually give and accept each other in order to establish a marriage" (c. 1057, § 2). This consent must be free, mutual and genuine; that is, by it each of the spouses must give himself or herself, and accept the other, in a relationship characterized by exclusiveness ('you and you alone'), permanence ('till death do us part') and procreativity (openness to the children with which God may bless their union). "Marriage is based on the consent of the contracting parties, that is, on their will to give themselves, each to the other, mutually and definitively, in order to live a covenant of faithful and fruitful love" (CCC 1662).
The two institutional purposes of marriage
To understand the nature of marriage, one has to go back to its institution by God. It is striking that the Bible, in the first and second chapters of the Book of Genesis, gives us two accounts of the creation of the sexes; together they reveal God's design for sexuality and marriage. Jesus himself, in trying to raise his Apostles' minds to a proper understanding of the original divine plan for the marital relationship, refers back to one of these accounts: "He who made them from the beginning made them male and female, and said, 'For this reason a man shall leave his father and mother and be joined to his wife, and the two shall become one'. So they are no longer two but one" (Mt 19:4-6). The words Jesus uses are taken from the second chapter of Genesis, where the creation of the sexes is presented in the context that since "it is not good for man - or woman - to be alone", God makes a "helper" or "helpmate" - a conjugal partner - for him or her (Gn 2:18-24).
So we find Our Lord himself drawing attention to what we would today term the "personalist" end of marriage: the goodness that comes to the spouses, in their growth as persons, from their being joined together in the conjugal bonded covenant.
The divine plan and purpose of marriage would remain incomplete if it were drawn only from chapter two of Genesis. The fullness of the plan of sexual differentiation is revealed in the complementary account, found in chapter one of the same book: "God created man in his own image, in the image of God he created him; male and female he created them. And God blessed them, and God said to them, 'Be fruitful and multiply'" (Gn 1:27-28). This passage describes the "procreational" end of marriage, just as chapter two (which biblical experts consider in fact to be earlier in date of composition) describes the "personalist" end. These ends, however, should not be overcontrasted. The personalist end is an "institutional" end (it derives from the institution of marriage) just as much as the procreational end. And the procreational end, properly understood, is also personalist (having children expresses marital love and "fulfills" the spouses). In the past, the hierarchy between the ends of marriage was stressed. Today the Church prefers to emphasize the interconnection and interdependence between them.
The Catechism of the Catholic Church, in harmony with the two biblical narrations just noted, speaks of "the twofold end of marriage: the good of the spouses themselves, and the transmission of life" (2363). The two ends, taken together, reveal God's overall plan in instituting marriage. Marriage is aimed at the perfecting of the spouses - their "good" - by fidelity to the bond of loving companionship and help between them, a bond with its physical expressions that naturally lead to the begetting of children, the most personalized fruit of their union and love.
These two institutional purposes of marriage - the "good of the spouses" and procreation/education of children - are intimately interlinked. By true conjugal-sexual self-donation, the spouses tend to become parents, and share in the enriching experience of self-perpetuation. By their dedication to their children they continue to grow individually as persons and in mutual esteem. At the same time the human race is perpetuated in a family way, children are born of love and are raised in an atmosphere where they can receive the guidance they need: firm and affectionate, inspiring respect rather than fear.
The possibility of having children is not to be seen as a merely biological consequence of the physical structure of sex. The power to procreate is a complement to human love, and a major expression and support of it. So it is totally inadequate to see human procreation in mere biological terms of the physical perpetuation of mankind. Allowing for the parallels between human and animal procreation, the profound differences between them must be properly noted. Animal procreation is normally the result of a casual and transient meeting of a male and a female. Human procreation is meant to take place in the setting of a stable lifelong relationship between a man and woman. The procreation of animals serves to perpetuate each species for as long as the world lasts. Human procreation brings into existence a being with an eternal soul, destined to live for ever as a child of God.
The act by which animals are conceived is no more than the satisfying of a physical urge or instinct of those who mate. The conception of a human person should be the fruit of mutual self-donation, of conscious marital love; it should be an act that signifies in a unique way the exclusive, life-long conjugal union of husband and wife.
A major problem today is the number of people who, when they marry, think that their mutual love is sufficient to make their marriage "fulfilling", and look on children - one or two children - as an optional factor that may help and enrich their married life, but might also be an obstacle to their self-fulfillment. "Family planning" then becomes "happiness planning" or "fulfillment planning", adding an element of calculation to conjugal love and union which is not likely to lead to the greater happiness that marriage promises.
A couple can stare the love out of each other's eyes, if they remain just looking at one another. Nature's plan is rather that, as romantic love uniting the spouses wanes, they learn to look together at their children, the incarnated fruit of their union, and to center their shared attention and concerns more and more on them.
The teaching of the Second Vatican Council on the universal call to holiness (Lumen Gentium, Ch. V) means that God has a particular and individual plan for every single person. He similarly has a particular plan for each married couple, and for the family their love naturally tends to form. Married couples do well to reflect that God is the wisest Natural Family Planner, and the Marriage Counselor with the longest experience. It is predictable that a marriage without children (when children can be had) or without the number of children God had planned for that marriage (one child, two, ten...) is not likely to conduce to the good of the spouses, fulfilling them in the measure God had in store for them.
The "good of the spouses"
The "good" that God seeks to draw from marriage for each of the spouses consists not merely in possible human satisfactions, but essentially in the maturing of husband and wife by persevering in the task of loving and caring for each other and their children over a life-time; "in good times and in bad", when it is easy and when it is tough.
True married love is beautiful, but not easy. We are all persons with defects, and it is never easy to love a defective person (only God finds no difficulty in that). What makes it particularly hard to love is not only the defects of others, but (even more so) our own defects, our self-concern, our pride, our sensuality. We all want and need to love; but it is something very hard for us to do in any true and lasting fashion. A poor capacity for loving - that is our most threatening defect.
Life here on earth is really about learning to love. And marriage (just as family life) is never properly understood unless it is seen and lived as a divine plan to help and teach people to love. That is why marriage, more than a "haven" of love, is meant to be a school of love. Every marriage being the binding together of two defective persons (as the spouses should expect, and as they certainly discover once initial and easy romantic love passes), the basic ground rule for any marriage which is to work becomes evident. It is (learning) to love one's partner with his or her defects, being content moreover to love with one's own defective love. "Learning to love" is always the big task of married people.
Learning to love, in marriage, is a process that never ends. As between husband and wife, it means learning to understand, to forgive, to ask forgiveness, to avoid judgments, to keep starting again after each failure, so that self-love is assumed and purified in conjugal love, and so that conjugal love becomes parental love.
Learning to love as parents has to be a joint endeavor, where husband and wife distribute responsibilities and sacrifices, and in particular try to create a home with a distinctive family personality that comes from the active and creative participation of each one involved - parents and children. In his "Letter to Families", Pope John Paul II said that families today lack life: "Families today have too little "human" life" (no. 10). Families need to have their own vitality. There has to be "family life" that the children also help to create, live by, and look forward to. Families with such a personality are not only the best safeguard for young people against negative or destructive elements in the social atmosphere, but become themselves focal points for gradually changing and renewing - humanizing -society.
In married life, husband and wife have equal dignity and rights, but different and complementary roles. Growing in love within marriage does not necessarily mean becoming more alike; it more often means becoming more distinct, each one more identified in his or her conjugal role, and so more capable of acting as complement to the other. The ability to complement one another also implies a growth on the part of each in sexual identity. If the husband does not grow in masculinity, and the wife in femininity, their union and complementarity will not grow either.
Married chastity
In a section entitled, "Marriage under the regime of sin", the Catechism speaks of how evil is also experienced "in the relationships between man and woman", which can be distorted into one "of domination and lust" (1606-1607). Spouses need the virtue of married chastity to preserve the purity of their love. Chastity is expressed not primarily by abstinence, but rather by the effort to purify the sexual act of an over self-centered or possessive attitude, so as to retain the tenderness of what is both a loving donation to the other as well as a spousal acceptance of him or her. For this, husband and wife need God's help: "Without his help, man and woman cannot achieve the union of their lives for which God created them 'in the beginning'" (CCC 1608).