The 10 Commandments – The 6th: “You Shall Not Commit Adultery”

By Father Reginald Martin, O.P.


The Sixth Commandment, like most of the others of the Second Tablet, is presented as a negative precept: “You shall not commit adultery.” But our Catechism turns to an Apostolic Exhortation of John Paul II and invites us to look at God’s word in a more positive light.

God is love and in himself he lives in a mystery of personal living communion. Creating the human race in his own image…. God inscribed in the humanity of man and woman the vocation, and thus the capacity and responsibility, of love and communion. (Familiaris Consortio, 11)


Placing our First Parents in the Garden, and giving them the commission to be fruitful and multiply, God laid the foundation for marriage, the family, and what eventually would become the complex network of social relations we call human society.

If we consider almost any advertisement we see today, read horrific newspaper accounts of sexual assaults, reflect that the United States is the world’s largest exporter of pornography, or even think about some of the random thoughts that cross our minds from time to time, we may be tempted to ask why God would lay the immense responsibility for the destiny of the human race at the door of human sexuality, but God’s Providence is mysterious, and the Catechism observes, “The harmony …of society depends in part on the way in which the complementarity, needs and human support between the sexes are lived out.” (CCC, #2333)


Our human sexuality, then, is an immense blessing, one that comes with a correspondingly high price, which is our human responsibility. The first act of this responsibility is to remember that man and woman are equally created in God’s image. Thus, the Catechism observes, quoting Pope Saint John Paul II, “God gives man and woman an equal personal dignity.” (CCC, # 2334)

This dignity is, perhaps, realized most visibly and completely in Christian marriage. The old admonition read to couples at their wedding ceremony reminded them that in the Sacrament of Matrimony, God

…gave to man a share in the greatest work of creation, the work of the continuation of the human race. And in this way he sanctified human love and enabled man and woman to help each other live as children of God, by sharing a common life under his fatherly care.

This is echoed in one form of the Nuptial Blessing, which relates that marriage joins woman to man

…and the companionship they had in the beginning is endowed with the one blessing not forfeited by original sin nor washed away by the flood.


A Dominican preacher once observed the soldiers at Calvary, casting lots for Jesus’ tunic, learned the same lesson Adam and Eve learned in the Garden: sin never got us anything but clothes. Yet even when our poorly-clad First Parents were cast out of Eden, they had one another. From this we conclude that human sexuality, ennobled by human love, remains a constant sign of God’s love and care for His people.

When St. Paul tells the Ephesians how husbands and wives ought to relate to one another, he describes marriage as the same relation that binds Christ to the Church.

Husbands love your wives, as Christ loved the Church and gave himself up for her…Even so, husbands should love their wives as their own bodies. He who loves his wife loves himself. For no man ever hates his own flesh, but nourishes and cherishes it, as Christ does the church….”For this reason a man shall leave his father and mother and be joined to his wife, and the two shall become one flesh.” This mystery is a profound one, and I am saying it refers to Christ and the church. (Eph 5:25-30)


This mystery is so profound were we to lose every other sign of God’s love, we would have the right to look at the married couples in our midst and say, “Ah, that mysterious something that keeps them in love with one another is the same mysterious grace that keeps Christ in love with us.” And the result, the Catechism teaches, is, indeed, the same: “The union of man and woman in marriage is a way of imitating in the flesh the Creator’s generosity and fecundity….” (CCC, #2335)


We miss the point of the Sixth Commandment, of course, if we imagine it applies only to those who are married. The chastity that must characterize, govern and guard a marriage is the same virtue calling each of us to a wholesome life. It provides the encouragement and protection we need as we progress along the way of perfection. Our Catechism teaches,

Chastity means the successful integration of sexuality within the person and thus the inner unity of man in his bodily and spiritual being. Sexuality, in which man’s belonging to the bodily and biological world is expressed, becomes personal and truly human when it is integrated into the relationship of one person to another…. (CCC, #2337)


In the present, this may realize its perfection in marriage, but the unselfish friendship modeled by Jesus is also an example here on earth of the eternal companionship we look forward to sharing with God’s elect in heaven. Chastity teaches us to give what is most God-like in us to others, so it forms the basis for the true, disinterested (which is altogether different from uninterested) friendship that seeks only the good of the other.


St. Thomas Aquinas teaches that the word Chastity is derived from the word “chastise,” and another writer echoes this when he observes that chastity, “the first means for attaining perfection…is the domination of the flesh and its appetites by the spirit.” Chastity chastises the will, teaching it to seek moderation in sexual behavior. Purity is a part of Chastity, moderating the pleasure we take from looking at or touching another person. Priests and members of religious communities who take vows, promise to give up their use of some of life’s legitimate pleasures. On the surface, such renunciation may resemble Insensibility, but we must distinguish between Insensibility’s scorn for what it pleasant and useful, and the commands of Chastity, by which an individual foregoes use of a legitimate good in an effort to keep her or his mind focused on another good. In an often-quoted passage from St. Paul, we read,

The unmarried woman and the virgin think on the things of the Lord: that she may be holy in both body and in spirit. But she that is married thinks on the things of the world, how she may please her husband. (1 Cor. 7:34)


The point is not that the choice of a celibate life is better than the decision to marry, but that the good things that accompany one choice necessarily preclude one’s choosing the other. Regardless of our choice to marry or embrace celibacy, chastity calls us to self-mastery and integrity. Our Catechism is seldom stern in its admonitions, but here it sounds almost threatening.

The chaste person maintains the integrity of the powers of life and love placed in him. This integrity ensures the unity of the person; it is opposed to any behavior that would impair it. It tolerates neither a double life nor duplicity in speech…the alternative is clear: either man governs his passions and finds peace, or he lets himself be dominated by them and becomes unhappy. (CCC, #2338, #2339)


Chastity is assisted and governed by the Virtue of Temperance, which, we have seen, helps us govern our appetites with reason. (CCC, #1809, #2341) This is not an overnight process; acquiring virtue is a life-long journey. And some virtues are more easily acquired than others. Temperance and Chastity, because they are so closely linked to taste and touch, may seem nearly impossible goals, and the Catechism remarks,

Self-mastery is a long and exacting work. One can never consider it acquired once and for all. It presupposes renewed effort at all stages of life. (CCC, #2342)


Prayer is essential in this task. So, too, is our effort to share with the world whatever personal progress we may have made in our spiritual growth. This might seem an odd consequence of Chastity, but here we must remember that Chastity requires us to respect the dignity of our fellow men and women. Our Catechism reminds us that because human sexuality is, ultimately, the foundation of human society, Chastity

…also involves a cultural effort, for there is an “interdependence between personal betterment and the improvement of society.” Chastity presupposes the rights of the person, in particular the right to receive information and an education that respects the moral and spiritual dimensions of human life. (CCC, #2344)


This reflects the sometimes overlooked (or undervalued) communal effect of Baptism, which not only cleanses us of Original Sin, but unites us to one another as members of Christ’s Body. Our Catechism devotes considerable space to its discussion of Baptism. It tells us that through Baptism, “we become members of Christ, are incorporated into the Church and made sharers in her mission.” (#1213) The text continues, “The whole ecclesial community bears some responsibility for the development and safeguarding of the grace given at Baptism.” (CCC, #1255) Furthermore,

[as] Baptism makes us members of the Body of Christ: “Therefore, we are members of one another,” Baptism incorporates us into the Church. From the baptismal font is born the one People of God of the New Covenant, which transcends all the natural or human limits of nations, cultures, races and sexes…. (CCC, #1267)


Chastity may seem an odd virtue to call upon as we consider our vocation as members of Christ’s Church, but St. Augustine reminds us, “…it is through chastity that we are gathered together and led back to the unity from which we were fragmented into multiplicity” by our choosing to sin. Through chastity, our Catechism teaches, the Holy Spirit enables those who have been baptized to imitate the purity of Christ. This purity manifests itself in diverse ways, as we shall note further on, but we see it reflected most generally in the non-threatening relations that characterize true friendships.


“People should cultivate [chastity] in the way that is suited to their state of life.” Thus the Vatican Congregation for the Doctrine of the Faith clearly states the universal obligation for each of us to embrace the chaste example of Our Savior. We have considered already some aspects of the sacrament of Matrimony. Let us now say a word about the sexual activity proper to the sacrament, which the Catechism observes

…is not something simply biological, but concerns the innermost being of the human person as such. It is realized in a truly human way only if it is an integral part of the love by which a man and woman commit themselves totally to one another until death. (#2361)

From this we should understand that the sexual pleasure spouses share with one another is an immense gift, intended to be a source of joy. Our theology teaches that a gift is never given simply to benefit the individual who receives it; rather gifts are given to enrich the entire community. This is the case with human sexuality. It unites husbands and wives to increase their fidelity to one another, and to enable them to carry out God’s command to our First Parents, “Be fruitful.”


Before his election as Pope, Joseph Ratzinger remarked the importance of memory, and identified Mary as “the embodiment of the Church’s memory.” This memory, he said, is “more than the kind of memory that stores telephone numbers: [it is] a memory of the heart, in which I invest something of myself.”

St. Luke’s is a particularly rich picture of Mary; he tells us three times she “kept” things in her heart, allowing them to shed light on the events of her life. In Mary we see a practical illustration of the community we share with one another, for in her we see our vocation as preachers. Once we say “yes” to God’s Word, we have no choice but to share it. The negative prohibition of the Sixth Commandment is quite daunting, but once we look beyond “you shall not,” we realize the command is an invitation to offer God something uniquely our own. And the result? God’s Word functions in our life much as the Eucharist. Everything else we eat becomes part of us, but in the Eucharist we are transformed into what we eat, and we become what we believe: the Body of Christ. Our encounter with God’s Word likewise transforms us. And that, Cardinal Ratzinger assures us, is how intellectual life and spiritual growth are handed on. “In other words, it is the only way to progress.”


The next issue of Light and Life will continue the discussion of the Sixth Commandment, and link its call to virtue to some reflections on Pope Francis’ heroic (and challenging) example of leadership of Church leadership in our time.

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