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For Your Marriage

Between Man and Woman

Why does the Catholic Church teach that marriage can exist only between a man and a woman?

Marriage, as both a natural institution and a sacred union, is rooted in God’s plan for creation. The truth that marriage can only exist between a man and a woman is woven deeply into the human spirit. The Church’s teaching on marriage expresses a truth, therefore, that can be perceived first and foremost by human reason. This truth has been confirmed by divine Revelation in Sacred Scripture.

Why can marriage exist only between a man and a woman?

The natural structure of human sexuality makes man and woman complementary partners for expressing conjugal love and transmitting human life. Only a union of male and female can express the sexual complementarity willed by God for marriage. This unique complementarity makes possible the conjugal bond that is the core of marriage.

Why is a same-sex union not equivalent to a marriage?

A same-sex union contradicts the nature and purposes of marriage. It is not based on the natural complementarity of male and female. It cannot achieve the natural purpose of sexual union, that is, to cooperate with God to create new life. Because persons in a same-sex union cannot enter into a true conjugal union, it is wrong to equate their relationship to a marriage.

What unique contributions does marriage between a man and woman make to society?

Marriage is the fundamental pattern for male-female relationships. It contributes to society because it models the way in which women and men live interdependently and commit to seek the good of each other. The marital union also provides the best conditions for raising children: namely, the stable, loving relationship of a mother and father present only in marriage. The state recognizes this relationship as a public institution in its laws because the relationship makes a unique and essential contribution to the common good.

Ideas about marriage have changed over the years. Isn’t same sex marriage just one more change?

The institution of marriage has experienced many developments. Some of these are related to our contemporary understanding about the equality of men and women. These developments have enhanced marriage, but none has conflicted with the basic purpose and nature of marriage. Proposals to legalize same sex marriage would radically redefine marriage.

If people of the same sex love and care for each other, why shouldn’t they be allowed to marry?

Love and commitment are key ingredients of marriage, and the Church recognizes that a basic purpose of marriage is the good of the spouses. The other purpose, however, is the procreation and education of children. There is a fundamental difference between marriage, which has the potential to bring forth children, and other relationships. Marriage between a man and a woman will usually result in children. This remains a powerful human reality, even if every marriage does not bring forth children. This makes marriage between a man and a woman a unique institution.

What difference would it make to married couples if same sex partners are allowed to marry?

We need to answer this question not simply as individuals, but as members of society, called to work for the common good. If same sex marriage were legalized, the result would be a significant change in our society. We would be saying that the primary purpose of marriage is to validate and protect a sexually intimate relationship. All else would be secondary. While we cannot say exactly what the impact of this change would be, experience suggests that it would be negative. Marriage would no longer symbolize society’s commitment to the future: our children. Rather, marriage would symbolize a commitment to the present needs and desires of adults.

Isn’t the Church discriminating against homosexual persons by opposing same sex unions?

No. Christians must give witness to the whole truth and, therefore, oppose as immoral both homosexual acts and unjust discrimination against homosexual persons.

It is not unjust to deny legal status to same-sex unions because marriage and same-sex unions are essentially different realities. In fact, justice requires society to do so.

The legal recognition of marriage, including benefits associated with it, is not only about personal commitment, but also about the social commitment that husband and wife make to the well-being of society. It would be wrong to redefine marriage for the sake of providing benefits to those who cannot rightfully enter into marriage. It should be noted that some benefits currently sought by persons in homosexual unions can already be obtained without regard to marital status. For example, individuals can agree to own property jointly, and they can generally designate anyone they choose to be a beneficiary of their will or to make health care decisions in case they become incompetent.

Where can I learn more about this issue?

The U.S. Conference of Catholic Bishops has launched an Initiative called “Marriage: Unique for a Reason.” Its purpose is to help educate and catechize Catholics on the meaning of marriage as the union of one man and one woman. Resources, including videos and catechetical materials, are available on the website.


Between Man and Woman: Questions and Answers About Marriage and Same-Sex Unions is a 2003 statement by the U.S. Conference of Catholic Bishops.

Other statements by the U.S. Conference of Catholic Bishops and the Vatican are available here.

The Massachusetts Catholic Conference has much information about this topic on its website.