In the Catholic version of the Decalogue, the Sixth and Ninth Commandments are coupled together. They both prescribe the practice of chastity.
The biblical text for the Sixth Commandment is simply You shall not commit adultery in both Exodus 20:14 and Deuteronomy 5:18. But the Ninth Commandment is part of a longer prohibition of covetousness.
You shall not covet your neighbors house. You shall not covet your neighbors wife or his servant, man or woman, or his ox or his donkey, or anything that is his (Exodus 20:17).
You shall not covet your neighbors wife, you shall not set your heart on his house, his field, his servant man or woman or his ox or his donkey, or anything that is his (Deuteronomy 5:21).
There is a basic similarity in these two prohibitions, but Deuteronomy places the command You shall not covet your neighbors wife first among the forms of greed which include property, cattle, and servants.
In pre-Christian Jewish morality, adultery rested on the idea that a wife was the property of the husband. Strictly speaking, therefore, only the husbands rights could be violated. Illicit intercourse was not really adultery if the woman was not married. Thus a wife and her partner could violate the rights of her husband, but the husband could not violate the rights of his wife. She had no marital rights to violate.
Old Testament morality forbade adultery both in act and in desire. But in both cases it was essentially a sin of injustice, along with stealing or coveting other possessions that a man might own.
New Testament Teaching
Jesus repeated the Sixth and Ninth Commandments but He elevated them in a way that has been the single most demanding precept of the New Law. His teaching is found in the Synoptic Gospels of Matthew, Mark, and Luke. St. Paul adds a great deal to the gospel narratives, so that the New Testament revelation on chastity is extraordinarily complete.
Unity and Indissolubility of Marriage. The heart of the Saviors doctrine on marital unity and indissolubility occurs in a dialogue He had with the Pharisees. They asked him if a man could put away his wife for any reason. This was meant to trap Jesus into taking sides with either the strict rabbis, who allowed divorce and remarriage only for adultery, or the liberal rabbis, who allowed it on any pretext whatever.
Instead of taking sides Jesus reminded the Pharisees that at the beginning of the human race, there was no divorce with the right to remarry. So then, He concluded, what God has united, man must not divide. To which the Pharisees objected that Moses permitted divorce and remarriage. Christ answered, It was because you were so unteachable. He then concluded, The man who divorces his wife I am not speaking of fornication and marries another, is guilty of adultery (Matthew 19:3-9).
What Christ meant by the phrase, I am not speaking of fornication, was that infidelity would justify a divorce, but not remarriage. This is plain from the parallel texts in St. Mark (10:2 12), St. Luke (16:18), and St. Paul (I Corinthians 7:10-39); Romans 7:2-3). St. Mark, a disciple of St. Peter, writing for converts from paganism, further mentions Christs saying that if a woman divorces her husband and marries another she is guilty of adultery too (Mark 10:12).
Jesus here elevated the Old Law by completely abrogating the practice of remarriage after divorce, which had been merely tolerated in the Mosaic Law.
Internal Chastity. Only St. Matthew records the Masters further raising the morality of the Decalogue. The Old Testament condemned the act of adultery and the sin of coveting another mans wife. But it considered internal adultery a sin of injustice. It did not precisely identify it as a sin against the virtue of temperance.
The difference between the two is important. To desire what belongs to someone else is wrong because it denies another persons rights to what he or she possesses. But to desire what God forbids me to enjoy is wrong because it denies His right to tell me how I am to use my faculties of body and soul. The full text in St. Matthew should be quoted.
You have heard it was said You must not commit adultery. But I say this to you: If a man looks at a woman lustfully, He has already committed adultery with her in his heart. If your right eye should cause you to sin, tear it out and throw it away; for it will do you less harm to lose one part of you than to have your whole body thrown into hell (Matthew 5:27-29).
Words could not be plainer. What the Catholic Church calls the Ninth Commandment forbids all lustful thoughts and desires. Pope John Paul II observed that this precept of Christ applies equally to men and women: Both genders must control their sexual desires. To control these desires requires practicing custody of all the senses, but especially of the eyes and touch.
Consecrated Chastity. The capstone of Jesus teaching on chastity occurs in the context of His restoring marriage to its original form of monogamy. He had just told the Pharisees that a man commits adultery if he puts away his wife and remarries.
The disciples said to Him, If that is how things are between husband and wife, it is not advisable to marry. But He replied, It is not everyone who can accept what I have said, but only to those to whom it is granted. There are eunuchs born that way from their mothers womb, there are eunuchs made so by men, and there are eunuchs who have made themselves that way for the sake of the kingdom of heaven. Let those accept this who can (Matthew 19:10-12)
Since apostolic times there have been men and women who did accept this teaching and who believed they had the necessary grace to sacrifice marriage for the sake of the kingdom of heaven.
The Church distinguishes two levels of Gods will in our regard. There are precepts binding on everyone under pain of sin; and there are counsels, inviting those who have the grace to do more for God.
Holiness is available to all followers of Christ in every state of life. And holiness, says the Second Vatican Council, is fostered in a special way by the manifold counsels which the Lord proposes to His disciples in the gospel for them to observe. This is where the counsel of dedicated chastity is part of Gods mysterious Providence.
Towering among these counsels is that precious gift of divine grace given to some by the Father to devote themselves to God alone more easily with an undivided heart in virginity or celibacy. This perfect continence for love of the kingdom of heaven has always been held in high esteem by the Church as a sign and stimulus of love, and as a singular source of spiritual fertility in the world (Constitution on the Church, V, 42).
The adverb always in the foregoing statement is proved by the Churchs history. Sacrifice of the experience of marriage has been part of Catholic Christianity since Christ set the pattern for His disciples.
Observance of Chastity
We see that there are three forms of chastity recognized by the Catholic Church. They may be called marital chastity, unmarried chastity, and consecrated chastity. Each has its own responsibilities and corresponding legislation by Church authority.
Marital chastity requires that husband and wife remain faithful to each other. It further requires that they do not deliberately interfere with the divinely ordained purpose of marital intercourse, which is the conception of a new human being.
Unmarried chastity requires that a person never deliberately arouses sexual pleasure, or willfully consents to the pleasure once it is aroused.
By assuming a life of perfect continence followers of Christ make the sacrifice of seeking marriage. They voluntarily give up what other unmarried persons may lawfully and laudably desire.
On all three levels the faithful practice of chastity is more than unaided human nature can accomplish. It calls for not only prayer but the spirit of prayer, which seeks to live in the presence of God. It requires the grace available through the sacraments of Penance and the Holy Eucharist. It demands watchful control of the senses. It exacts constant vigilance over the emotions and the imagination. And it must be built on a sincere humility, which has no illusions about ones own strength but relies on the power of God.
Sins of Unchastity
Chastity, it is said, takes its name from the fact that reason enlightened by faith, chastises concupiscence. Since concupiscence is the irrational desire of our fallen human nature, it needs to be curbed.
Among our irrational desires is the urge for sexual pleasure outside of marriage. And even in marriage, the sex drive needs to be constantly restrained.
Failure to control sexual desires goes by the general name of unchastity. But immediately we should distinguish two different kinds of unchastity. They are given different names depending on whether in sinning, natures purpose of sex can be attained, or whether this purpose is frustrated. If the purpose is attainable, they are called natural sins against chastity. Otherwise the sins are said to be unnatural.
Fornication and Adultery.There are two principal so-called natural sins against chastity, namely fornication and adultery. In both cases conception can take place and a child can be born. In that sense the sins are natural. But they are grave sins.
In fornication there is voluntary sexual intercourse between unmarried persons who are not bound by celibacy or a vow of consecrated chastity. If the persons are closely related to one another by blood, there is the further sin of incest. If either is under dedicated celibacy or chastity, they also commit a sacrilege.
The sinfulness of fornication lies in several facts. Those who indulge in sexual intercourse outside of marriage sin by injustice against each other. Neither partner has the loving and lifetime commitment that only marriage can provide. If they are baptized, neither has the divine blessing and supernatural grace assured by the sacrament of Matrimony. If a child is conceived and born, it does not have the security, stability, and selfless care that only a married father and mother can give. And society is destabilized by the bad example that fornication gives to others, especially the young. The basis of civilized society is shaken because the foundation of a sound society is a dedicated family, whereas by definition those indulging in fornication are not dedicated to each other by a permanent marriage bond.
Adultery is sexual intercourse with the husband or wife of a third person. Its sinfulness includes all the evils we have just seen in fornication, and others besides. Those who commit adultery, sin gravely against the rights of the husband or wife to whom they are married. The literature of all nations is filled with accounts of what adultery does to once happily married spouses. Murders and suicides have been provoked, even wars have been fought to avenge the crime of adultery. Not a small degree of emotional disturbance and mental breakdown can be traced to the crushing impact on the human personality caused by the adulterous behavior of a once devoted spouse.
Masturbation, Contraception and Homosexuality. The unnatural sins of unchastity are against the divinely ordained nature of sexual intercourse, which is to reproduce the human race.
Masturbation is the deliberate arousal of sexual pleasure caused by some form of self-stimulation. It is also called self-abuse, and is gravely sinful when fully conscious and indulged with full consent of the will.
Contraception is any action deliberately taken before, during, or after intercourse to prevent conception or fetal development. Contraception is gravely sinful because it contradicts the divinely intended purpose of marital intercourse, which is to foster procreative love.
As with abortion, so contraception has been consistently condemned by the Catholic Church from her earliest history. When Pope Paul VI published Humanae vitae (July 25, 1968), he stated that the teaching of the Church on the regulation of birth simply promulgates the divine law. This law is first of all the law of nature which can be recognized by the light of reason. One of the most compelling reasons against contraception is the record of history. Humanae vitae gives some of the known and predictable results of contraception.
The road is opened to conjugal infidelity and to the general lowering of morality.
Men tend to lose respect for their wives, no longer caring for their physical and psychological welfare.
Men tend to look on their wives as mere instruments of selfish enjoyment.
Men tend no longer to look on their wives as beloved companions.
Given the widespread practice of contraception, some have questioned whether the Churchs teaching on this grave moral issue is open to change. Pope Pius XI took issue with these dissenters in the clearest possible terms:
Openly departing from the uninterrupted Christian tradition, some recently have judged it possible solemnly to declare another doctrine on this question
The Catholic Church, to whom God has entrusted the defense and purity of morals, standing erect in the midst of the moral ruin which surrounds her, in order that she may preserve the chastity of the marital union from being defiled by this foul stain, raises her voice in token of divine Ambassadorship and through Our mouth proclaims anew: Any use whatsoever of matrimony exercised in such a way that the act is deliberately frustrated in its natural power to generate life is an offense against the law of God and of nature, and those who indulge in such are branded with the guilt of a grave sin (Casti Connubii, December 31, 1930).
Such will therefore always be the teaching of the Catholic Church. Her doctrine on contraception is irreversible.
One form of contraception that is becoming widespread is direct sterilization. This means that the body is deliberately deprived, either temporarily or permanently, of its power to beget or to bear children. The morality of contraceptive sterilization is to be judged in the same way as artificial birth control or contraception.
Homosexuality is any form of sexual relationship among persons of the same sex. A homosexual tendency is within the normal range of any human being. Given our fallen human nature, such a tendency is not unusual but must be recognized for what it is, contrary to divine law.
Homosexual attraction may be due to an individuals personality. More often it is the result of indiscretion or seduction. Not sinful by itself, the sexual attraction must be resisted.
Homosexual activity is the result of voluntarily giving in to the tendency or attraction. It is gravely sinful and has been explicitly condemned in Sacred Scripture. St. Paul describes the pagans of his day as having refused to honor God:
That is why God has abandoned them to degrading passions: why their women have turned from natural intercourse to unnatural practices and why their menfolk have given up natural intercourse to be consumed with passion for each other, men doing shameless things with men and getting an appropriate reward for their perversion (Romans 1:26-27).
Historians of the Roman Empire in St. Pauls day testify to the fact that homosexual vice had sunk into a state of extreme laxity. In the apostles words, since they refused to see it as rational to acknowledge God, God has left them to their own irrational ideas and to their monstrous behavior (Romans 1:28).
There is a tragic logic in the relation between indifference to God and sexual immorality. Those who refuse to bend their minds in the humble worship of God do not receive the grace to keep their passions under rational control.
Natural Family Planning
Already in apostolic times, husbands and wives would abstain from marital relations only for an agreed time, to leave yourselves free for prayer (I Corinthians 7:1, 4-5).
With the rise of a contraceptive mentality in modern times, the Church has more than once returned to the subject of periodic continence or, as it is popularly called, natural family planning. On Catholic moral principles, a couple may for a good reason abstain from intercourse during the wifes fertile periods. Married people, the Church tells them, may renounce the use of marriage when for just motives, procreation is not desirable. They make use of it during the sterile periods to manifest their affection and to safeguard their mutual fidelity. By so doing, they give proof of a truly and fully praiseworthy love (Paul VI, Humanae vitae, II, 16).
This is morally permissible, and oftentimes commendable because there is no interference with the purpose of marital intercourse. It is rather, in the Churchs language, making legitimate use of a disposition provided by the Author of nature.
Copyright © 2002 Inter Mirifica
Pocket Catholic Catechism