In the second part of Gaudium et Spes, the Vatican II Fathers discuss some of the “more urgent problems” facing the world today and illuminate them with the light of Christ. Each of the five chapters in the second part focuses on a particular issue relevant to the modern world: marriage and family, culture, economic and social life, the political community, and peace and international communion.
Here are some of the topics and ideas you'll find in Part II, Chapter I, of Gaudium et Spes.
Chapter I – The Dignity of Marriage and the Family
Marriage and the Family in the Modern World
* Healthy marriages and healthy families lead to healthy individuals and healthy societies.
* Marriage and family life are greatly threatened in the modern world, but the Church upholds and fosters the “dignity and supremely sacred value” of marriage.
Holiness of Marriage and the Family
* God is the Author of marriage, which is an “intimate partnership of life and love” between a man and a woman that is created by “their irrevocable personal consent” and governed by divine law.
* Marriage is for the good of the partners, who “mutually surrender themselves to each other.”
* Marriage is also “by its very nature...ordered to the procreation and education of offspring.” In children, marriage finds it “crowning glory.”
* Marriage is modeled on Christ's union with the Church. Because it is consecrated through a sacrament, marriage is also an encounter with Christ.
* The graces of marriage allow the couple to strive toward holiness and self-giving love, for “authentic married love is caught up into divine love.”
* Children contribute “to the sanctification of their parents” and must show affection, trust, and gratitude toward their parents.
* The Christian family manifests Christ to the world.
* The “intimate and chaste union” of husband and wife is a physical expression of their faithful, self-giving love. It is “noble and honorable” and has a unique dignity.
* Spouses share “equal personal dignity” and must show “outstanding courage” to fulfill their vocation. They do, however, have God's grace to help them live out their witness to the “faithfulness and harmony” of love.
The Fruitfulness of Marriage
* Children are the “supreme gift” of marriage.
* In their fruitfulness, married couples cooperate in God's creative work. Their “proper mission” is “to transmit human life and to educate their children.”
* Couples have the responsibility to discern the number and spacing of their children, using lawful methods and being ruled by conscience before God. They should be both prudent and generous in their decisions.
Married Love and Respect for Human Life
* The “transmission of life and the fostering of authentic married love” must always be practiced in obedience to the divine law.
* “Life must be protected with the utmost care from the moment of conception...”
* Sexuality should be treated with the greatest reverence in accord with “authentic human dignity.”
* Couples must follow the objective moral law in matters of birth regulation. They are forbidden to use methods condemned by the Church.
Fostering Marriage and the Family: A Duty for All
* The family is “a school of human enrichment,” for parents educate their children to follow their proper vocation in life with dignity and love.
* The family is the “basis of society,” and everyone has the responsibility to guard and foster family life and family values.
* Civil authorities must protect marriage and family in order to “safeguard public morality and promote domestic prosperity.”
* Christians promote marriage and family through their witness and “concerted action.”
* Priests, too, assist married couples and families through their pastoral care and teaching.
* Married couples are called to bear witness to their vocation and to the mystery of their self-giving love, which shares in the mystery of God's self-giving love.
The full text of Gaudium et Spes is available online at the Vatican website.