Sex Outside Marriage - AdobeStock_271170291Question: Why is it preachers say sex outside marriage is sexual immorality? The Greek word porneia means harlotry, or idolatry. So how is it that Leviticus 18 states sexual immorality and sex outside of marriage is not listed? Where does it specifically say in the Bible sex outside marriage is wrong?


Marriage is honorable among all, and the bed undefiled; but fornicators and adulterers God will judge.(Hebrews 13:4)

We preachers state that sex outside of marriage is wrong. But that is because it is our duty to teach as God decreed.

If anyone speaks, let him speak as the oracles of God. If anyone ministers, let him do it as with the ability which God supplies, that in all things God may be glorified through Jesus Christ, to whom belong the glory and the dominion forever and ever. Amen.(I Peter 4:11)


Do you not know that the unrighteous will not inherit the kingdom of God? Do not be deceived. Neither fornicators, nor idolaters, nor adulterers, nor homosexuals, nor sodomites, nor thieves, nor covetous, nor drunkards, nor revilers, nor extortioners will inherit the kingdom of God.(I Corinthians 6:9-10)

Sex Outside Marriage Arguments

So, let’s analyze your arguments. You claim that the Greek word porneia means idolatry or harlotry, a definition counter to every Greek lexicon of which I know, yet you offer no evidence that your restrictive meaning is true. A claim alone is not evidence.

Porneia, noun: Unchasity, prostitution, fornication, and immorality

Used in Matthew 5:32; 15:19: 19:9; Mark 7:21; John 8:41; Acts 15:20; 15:29; 21:25; Romans 1:29; I Corinthians 5:1; 6:13; 6:18; 7:2; II Corinthians 12:21; Galatians 5:19; Ephesians 5:3; Colossians 3:5; I Thessalonians 4:3; Revelation 2:21; 9:21; 14:8; 17:2, 4; 18:3; 19:2

Sex Outside Marriage Usage

Classical Greek: Porneia, which is relatively rare in classical Green (Moulton-Milligan), originally stood for “prostitution” (cf. porne, “prostitute”). In other, later contexts it denotes “unchasity, illicit sexual relations” of any kind (“fornication” is a somewhat archaic but common translation). Metaphorically, especially in Biblical writings, porneia means idolatry.

Septuagint Usage: Various forms of the stem zanah (“illicit intercourse”) are rendered by porneia in the Septuagint where two uses predominate. Literally, porneia means “prostitution, illicit intercourse, habitual sexual immorality.” Metaphorically, porneia stands for religious idolatry.


New Testament Usage: The New Testament continues the metaphoric understand in some texts. Revelation, in particular, uses the imagery of licentious sexual behavior (porneia) as a figure of religious idolatry. … Literal uses of porneia include a reference in Jesus’ teaching on divorce. Porneia (“habitual sexual immorality”; illicit sex; cf. moicheia, “adultery”) is the sole justifiable cause for divorce (Matthew 19:9; cf 5:32). Porneia is closely related to moicheia (Matthew 15:19; Mark 7:21); both come from the heart.

References: Strong 4202, Bauer 693, Moulton-Milligan 529, Kittel 6:579-95, Liddell-Scott 1450, Colin Brown 1:496-97,499-501.

Porneuo, verb: To prostitute, commit sexual immorality. Used in I Corinthians 6:18; 10:8; Revelation 2:14, 20; 17:2; 18:3, 9.

And then there is:

Classical Greek and Septuagint Usage: In classical Greek porneuo is used to describe sexual intercourse outside of marriage. The papyri follow this classical usage. The Septuagint uses porneuo literally in a few instances (Deuteronomy 23:17; Hosea 3:3; Amos 7:17). More often the term is used metaphorically for idolatry (see Hosea 4:10,13,18, for examples).

New Testament Usage: … Paul used the term literally in reference to the problem of sexual immorality in the Corinthian church. John used porneuo both literally of those who committed “fornication” (Revelation 2:14,20) and metaphorically of those who had united themselves with the “Great Harlot” (17:81), with merchandise (18:2f.; 19:2), and with those who persecute the saints (17:6).

References: Strong 4203, Bauer 693, Moulton-Milligan 529, Kittel 6:579-95, Liddell-Scott 11450, Colin Brown 1:497

Pornos, noun: Fornicator, immoral person.

Used in I Corinthians 5:9-11; 6:9; Ephesians 5:5; I Timothy 1:10; Hebrews 12:16; 13:4; Revelation 21:8; 22:15

Usage: This term was first used in classical Greek of one who had sexual intercourse with prostitutes. It also refers to male prostitutes. In the New Testament it carries the broader meaning of a fornicator, one who practices sexual immorality or who is clearly an immoral person (I Corinthians 5:9,11; Hebrews 12:16). In I Corinthians 6:9 and Hebrews 13:4 pornos is differentiated from moichos (a more narrow word used for an adulterer), thus indicating a person who is habitually or frequently involved in illegitimate sexual activities.

Such a person, who is classified together with other sinners (Ephesians 5:5; I Timothy 1:10; Revelation 21:8; 22:15), will be excluded from the kingdom of God (I Corinthians 6:9; Galatians 5:19-21).

References: Strong 4205, Bauer 693, Moulton-Milligan 529, Kittel 6:579-95, Liddell-Scott 1450, Colin Brown 1:497 [The Complete Biblical Library: Greek-English Dictionary]

More Sex Outside Marriage Explanations

Perhaps you don’t know the definition of “fornication” since it not popularly used in America these days.
Fornication Voluntary sexual intercourse between persons not married to each other Fornication is a term, which refers to sexual intercourse between consenting unmarried partners… Sexual intercourse between two unmarried peoples to have unlawful sexual intercourse. The incontinence or lewdness of unmarried persons, male or female.

Thus, we see that your definition is at best incomplete; porneia and related words are not exclusively used for harlotry and idolatry as you attempted to imply. You are attempting to deceive others by artificially narrowing information to make your cause seem to be supported.

Now the works of the flesh are evident, which are: adultery, fornication, uncleanness, lewdness, idolatry, sorcery, hatred, contentions, jealousies, outbursts of wrath, selfish ambitions, dissensions, heresies, envy, murders, drunkenness, revelries, and the like; of which I tell you beforehand, just as I also told you in time past, that those who practice such things will not inherit the kingdom of God.(Galatians 5:19-21)

Your second argument is of the same style. You selected a chapter, which mostly lists relationships which are forbidden and then claim that because sex outside of marriage, in general, is not mentioned in this particular chapter it implies it wasn’t forbidden at all.


Moreover, you shall not lie carnally with your neighbor’s wife, to defile yourself with her.(Leviticus 18:20)

The man who commits adultery with another man’s wife, he who commits adultery with his neighbor’s wife, the adulterer and the adulteress, shall surely be put to death.(Leviticus 20:10)


If a man is found lying with a woman married to a husband, then both of them shall die-the man that lay with the woman, and the woman; so you shall put away the evil from Israel.(Deuteronomy 22:22)

Fornication with Someone Engaged:

If a young woman who is a virgin is betrothed to a husband, and a man finds her in the city and lies with her, then you shall bring them both out to the gate of that city, and you shall stone them to death with stones, the young woman because she did not cry out in the city, and the man because he humbled his neighbor’s wife; so you shall put away the evil from among you.

But if a man finds a betrothed young woman in the countryside, and the man forces her and lies with her, then only the man who lay with her shall die. But you shall do nothing to the young woman; there is in the young woman no sin deserving of death; for just as when a man rises against his neighbor and kills him, even so is this matter. For he found her in the countryside, and the betrothed young woman cried out; but there was no one to save her.(Deuteronomy 22:23-27)

Fornication with Someone Uncommitted:

If a man entices a virgin who is not betrothed, and lies with her, he shall surely pay the bride-price for her to be his wife. If her father utterly refuses to give her to him, he shall pay money according to the bride-price of virgins.(Exodus 22:16-17)


If a man finds a young woman who is a virgin, who is not betrothed, and he seizes her and lies with her, and they are found out, then the man who lay with her shall give to the young woman’s father fifty shekels of silver, and she shall be his wife because he has humbled her; he shall not be permitted to divorce her all his days.(Deuteronomy 22:28-29)

You asked where it was forbidden, and numerous passages were cited above. So, in case these weren’t enough:

I wrote to you in my epistle not to keep company with sexually immoral people. Yet I certainly did not mean with the sexually immoral people of this world, or with the covetous, or extortioners, or idolaters, since then you would need to go out of the world. But now I have written to you not to keep company with anyone named a brother, who is sexually immoral, or covetous, or an idolater, or a reviler, or a drunkard, or an extortioner — not even to eat with such a person. For what have I to do with judging those also who are outside? Do you not judge those who are inside? But those who are outside God judges. Therefore ‘put away from yourselves the evil person.‘” (I Corinthians 5:11-13)

Additionally, it is written:

But fornication and all uncleanness or covetousness, let it not even be named among you, as is fitting for saints; neither filthiness, nor foolish talking, nor coarse jesting, which are not fitting, but rather giving of thanks. For this you know that no fornicator, unclean person, nor covetous man, who is an idolater, has any inheritance in the kingdom of Christ and God. Let no one deceive you with empty words, for because of these things the wrath of God comes upon the sons of disobedience. Therefore, do not be partakers with them.(Ephesians 5:3-7)

For I fear lest, when I come, I shall not find you such as I wish, and that I shall be found by you such as you do not wish; lest there be contentions, jealousies, outbursts of wrath, selfish ambitions, back-bitings, whisperings, conceits, tumults; lest, when I come again, my God will humble me among you, and I shall mourn for many who have sinned before and have not repented of the uncleanness, fornication, and lewdness which they have practiced.(2 Corinthians 12:20-21)

Therefore, put to death your members which are on the earth: fornication, uncleanness, passion, evil desire, and covetousness, which is idolatry. Because of these things the wrath of God is coming upon the sons of disobedience.(Colossians 3:5-6)

Also note:

For this is the will of God, your sanctification: that you should abstain from sexual immorality; that each of you should know how to possess his own vessel in sanctification and honor, not in passion of lust, like the Gentiles who do not know God.(I Thessalonians 4:3-5)

More Sex Outside Marriage Insights

You keep referring to sexual immorality as sex outside of marriage, yet you keep referring to adultery. Look up porneia, on Wesley web site. Why would God care if I’m in a monogamous relationship and no one is in my bedroom? Do I need to show you the meaning of porneia? Seems to me to be prostitution or idolizing other gods.

And He said, ‘Go, and tell this people: Keep on hearing, but do not understand; keep on seeing, but do not perceive.’ Make the heart of this people dull, and their ears heavy, and shut their eyes; lest they see with their eyes, and hear with their ears, and understand with their heart, and return and be healed.’ Then I said, ‘Lord, how long?’ And He answered: ‘Until the cities are laid waste and without inhabitant, the houses are without a man, the land is utterly desolate.’(Isaiah 6:9-11)


But even the attempt at distraction fails:

“… The word porneia signifying unchastity in general, either in the married or unmarried state…” [John Wesley, “Upon Our Lord’s Sermon on the Mount, 3”, Sermon No. 23].

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