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State of the Question


Fornication is carnal union between an unmarried man and an unmarried woman. The euphemisms “hooking-up,” “shacking-up,” and “living together” phenomena are frequently occasions of fornication.


Divine Revelation


Deuteronomy 22:23-27

If within the city a man comes upon a maiden who is betrothed, and has relations with her,  you shall bring them both out to the gate of the city and there stone them to death: the girl because she did not cry out for help though she was in the city, and the man because he violated his neighbor's wife. Thus shall you purge the evil from your midst. "If, however, it is in the open fields that a man comes upon such a betrothed maiden, seizes her and has relations with her, the man alone shall die.  You shall do nothing to the maiden, since she is not guilty of a capital offense. This case is like that of a man who rises up against his neighbor and murders him: it was in the open fields that he came upon her, and though the betrothed maiden may have cried out for help, there was no one to come to her aid.


Hosea 4:11

Fornication, and wine, and drunkenness, take away the understanding. My people have consulted their stocks, and their staff has declared unto them: for the spirit of fornication has deceived them, and they have committed fornication against their God. They offered sacrifice upon the tops of the mountains, and burnt incense upon the hills: under the oak, and the poplar, and the turpentine tree, because the shadow thereof was good: therefore shall your daughters commit fornication, and your spouses shall be adulteresses. I will not visit upon your daughters, when they shall commit fornication and upon your spouses when they shall commit adultery: because themselves conversed with harlots, and offered sacrifice with the effeminate, and the people that does not understand shall be beaten.


Wisdom 14:12

For the source of wantonness is the devising of idols; and their invention, a corruption of life.


Matthew 15:19

But the things that come out of the mouth come from the heart, and they defile. For from the heart come evil thoughts, murder, adultery, unchastity, theft, false witness, blasphemy.


Galatians 5:19-21

Now the works of the flesh are obvious: immorality, impurity, licentiousness, idolatry, sorcery, hatreds, rivalry, jealousy, outbursts of fury, acts of selfishness, dissensions, factions,  occasions of envy,  drinking bouts, orgies, and the like. I warn you, as I warned you before, that those who do such things will not inherit the kingdom of God.


1 Corinthians 6:9

Do you not know that the unjust will not inherit the kingdom of God? Do not be deceived; neither fornicators nor idolaters nor adulterers nor boy prostitutes nor practicing homosexuals


Colossians 3:5

Put to death, then, the parts of you that are earthly immorality, impurity, passion, evil desire, and the greed that is idolatry.


Hebrews 12:15, 16

See to it that no one be deprived of the grace of God, that no bitter root spring up and cause trouble, through which many may become defiled, that no one be an immoral or profane person like Esau, who sold his birthright for a single meal.


Ephesians 5:3-5

Immorality or any impurity or greed must not even be mentioned among you, as is fitting among holy ones,


1 Corinthians 5:9-13

I wrote you in my letter not to associate with immoral people, not at all referring to the immoral of this world or the greedy and robbers or idolaters; for you would then have to leave the world. But I now write to you not to associate with anyone named a brother, if he is immoral, greedy, an idolater, a slanderer, a drunkard, or a robber, not even to eat with such a person. For why should I be judging outsiders? Is it not your business to judge those within? God will judge those outside. “Purge the evil person from your midst.”


1 Corinthians 6:18-20)

Avoid immorality. Every other sin a person commits is outside the body, but the immoral person sins against his own body. Do you not know that your body is a temple of the holy Spirit within you, whom you have from God, and that you are not your own? For you have been purchased at a price. Therefore, glorify God in your body.


1Thessolonians 4:3-7

This is the will of God, your holiness: that you refrain from immorality, that each of you know how to acquire a wife for himself in holiness and honor, not in lustful passion as do the Gentiles who do not know God; not to take advantage of or exploit a brother in this matter, for the Lord is an avenger in all these things, as we told you before and solemnly affirmed. For God did not call us to impurity but to holiness.


Romans 1:28-32

And since they did not see fit to acknowledge God, God handed them over to their undiscerning mind to do what is improper. They are filled with every form of wickedness, evil, greed, and malice; full of envy, murder, rivalry, treachery, and spite. They are gossips and scandalmongers and they hate God. They are insolent, haughty, boastful, ingenious in their wickedness, and rebellious toward their parents. They are senseless, faithless, heartless, ruthless.  Although they know the just decree of God that all who practice such things deserve death, they not only do them but give approval to those who practice them.


1 Timothy 9-10

We know that the law is good, provided that one uses it as law, with the understanding that law is meant not for a righteous person but for the lawless and unruly, the godless and sinful, the unholy and profane, those who kill their fathers or mothers, murderers, the unchaste, sodomites, kidnapers, liars, perjurers, and whatever else is opposed to sound teaching, according to the glorious gospel of the blessed God, with which I have been entrusted.


2 Timothy 2-5

So turn from youthful desires and pursue righteousness, faith, love, and peace, along with those who call on the Lord with purity of heart. … But understand this: there will be terrifying times in the last days. People will be self-centered and lovers of money, proud, haughty, abusive, disobedient to their parents, ungrateful, irreligious, callous, implacable, slanderous, licentious, brutal, hating what is good, traitors, reckless, conceited, lovers of pleasure rather than lovers of God, as they make a pretense of religion but deny its power. Reject them. For some of these slip into homes and make captives of women weighed down by sins, led by various desires, always trying to learn but never able to reach a knowledge of the truth.


Catechism of the Catholic Church


1852. There are a great many kinds of sins. Scripture provides several lists of them. The Letter to the Galatians contrasts the works of the flesh with the fruit of the Spirit: “Now the works of the flesh are plain: fornication, impurity, licentiousness, idolatry, sorcery, enmity, strife, jealousy, anger, selfishness, dissension, factions, envy, drunkenness, carousing, and the like. I warn you, as I warned you before, that those who do such things shall not inherit the Kingdom of God.”


2353. Fornication is carnal union between an unmarried man and an unmarried woman. It is gravely contrary to the dignity of persons and of human sexuality which is naturally ordered to the good of spouses and the generation and education of children. Moreover, it is a grave scandal when there is corruption of the young.


2396. Among the sins gravely contrary to chastity are masturbation, fornication, pornography, and homosexual practices.


2517. The heart is the seat of moral personality: 'Out of the heart come evil thoughts, murder, adultery, fornication....'[Matthew 15:19 .] The struggle against carnal covetousness entails purifying the heart and practicing temperance: Remain simple and innocent, and you will be like little children who do not know the evil that destroys man's life. [Pastor Hermae, Mandate 2, 1: PG 2, 916.]


2534. The tenth commandment unfolds and completes the ninth, which is concerned with concupiscence of the flesh. It forbids coveting the goods of another, as the root of theft, robbery, and fraud, which the seventh commandment forbids. 'Lust of the eyes' leads to the violence and injustice forbidden by the fifth commandment. [Cf. 1John 2:16; Micah 2:2] Avarice, like fornication, originates in the idolatry prohibited by the first three prescriptions of the Law. [Cf. Wisdom 14:12] The tenth commandment concerns the intentions of the heart; with the ninth, it summarizes all the precepts of the Law.

The Magisterium of the Church

Persona Humana: Declaration on Certain Questions Concerning Sexual Ethics
Sacred Congregation for the Doctrine of the Faith, December 29th, 1975

Today there are many who vindicate the right to sexual union before marriage, at least in those cases where a firm intention to marry and an affection which is already in some way conjugal in the psychology of the subjects require this completion, which they judge to be connatural. This is especially the case when the celebration of the marriage is impeded by circumstances or when this intimate relationship seems necessary in order for love to be preserved.

This opinion is contrary to Christian doctrine, which states that every genital act must be within the framework of marriage. However firm the intention of those who practice such premature sexual relations may be, the fact remains that these relations cannot ensure, in sincerity and fidelity, the interpersonal relationship between a man and a woman, nor especially can they protect this relationship from whims and caprices. Now it is a stable union that Jesus willed, and He restored its original requirement, beginning with the sexual difference. "Have you not read that the Creator from the beginning made them male and female and that He said: This is why a man must leave father and mother, and cling to his wife, and the two become one body? They are no longer two, therefore, but one body. So then, what God has united, man must not divide." St. Paul will be even more explicit when he shows that if unmarried people or widows cannot live chastely they have no other alternative than the stable union of marriage: ". . .it is better to marry than to be aflame with passion." Through marriage, in fact, the love of married people is taken up into that love which Christ irrevocably has for the Church, while dissolute sexual union defiles the temple of the Holy Spirit which the Christian has become. Sexual union therefore is only legitimate if a definitive community of life has been established between the man and the woman.

This is what the Church has always understood and taught, and she finds a profound agreement with her doctrine in men's reflection and in the lessons of history.


Ecclesiastical Tradition  


St. Ambrose of Milan (340-397) On Repentance, 60.

What the Apostle (St. Paul) means by the rod is shown by his invective against fornication, his denunciation of incest, his reprehension of pride, because they were puffed up who ought rather to be mourning, and lastly, his sentence on the guilty person, that he should be excluded from communion, and delivered to the adversary, not for the destruction of the soul but of the flesh. For as the Lord did not give power to Satan over the soul of holy Job, but allowed him to afflict his body, so here, too, the sinner is delivered to Satan for the destruction of the flesh, that the serpent might lick the dust of his flesh, but not hurt his soul.


St. John Cassian  (ca. 360 – 435) Conferences , Conference 5: 2

There are eight principal faults which attack mankind; viz., first gastrimargia, which means gluttony, secondly fornication, thirdly philargyria, i.e., avarice or the love of money, fourthly anger, fifthly dejection, sixthly acedia, i.e., listlessness or low spirits, seventhly cenodoxia, i.e., boasting or vainglory; and eighthly pride.


St. Basil of Caesarea (329 or 330 –  379) Letters,  Letter 199: XVI.

Fornication is not wedlock, nor yet the beginning of wedlock. Wherefore it is best, if possible, to put asunder those who are united in fornication. If they are set on cohabitation, let them admit the penalty of fornication.


The Teaching of the Fathers and Doctors of the Church

St. John Chrysystom, (c. 347–407)  Homily 15 on First Corinthians.

“It is actually reported that there is fornication among you, and such fornication as is not even named among the Gentiles, that one of you has his father's wife. And you are puffed up, and did not rather mourn, that he that had done this deed might be taken away from among you.For had it not been for the great wrath of which he was full, had he not been setting himself against them all, he would have spoken thus: Having heard that such and such a person has committed fornication, I charge you to punish him.

St. Thomas Aquinas (1225 – 1274) Summa Theologica, STh., II-II q.154 a.2 obj.6

On the contrary, It is written (Tobit 4:13): "Take heed to keep thyself . . . from all fornication, and beside thy wife never endure to know a crime." Now crime denotes a mortal sin. Therefore fornication and all intercourse with other than one's wife is a mortal sin. Further, nothing but mortal sin debars a man from God's kingdom. But fornication debars him, as shown by the words of the Apostle (Galatians 5:21), who after mentioning fornication and certain other vices, adds: "They who do such things shall not obtain the kingdom of God." Therefore simple fornication is a mortal sin.

Human Reason

In His Wisdom, God condemns fornication-- sexual intercourse outside marriage. What would be the objection that God would have with in indiscriminate sexual relations without marriage?

A primary reason may well be that an unwanted child/unplanned child/an illegitimate child  will not have the guarantee of the care and comfort of married parents, a good home environment, nurturing and caring by a person of each sex, education and faith-nurturing, etc., those stages  of life that occur naturally in a marriage relationship. Second, some respond with the objection that contraceptives will eliminate conception. That naive response ignores the fact of failure of all contraceptives at time; no contraceptive is 100% safe. Even with the possibility of contraception, the sexual passion of the moment often precludes taking the time to prepare a contraceptive. An unwanted conception then appeals an abortion far too often. God does know what He is doing when asking of His creatures.

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Unless otherwise noted, all Scripture texts are taken from the New American Bible with Revised New Testament and Revised Psalms © 1991, 1986, 1970 Confraternity of Christian Doctrine, Washington, D.C. and are used by permission of the copyright owner. All Rights Reserved. No part of the New American Bible may be reproduced in any form without permission in writing from the copyright owner.


© 2012 Robert J. Schihl


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