"Flee fornication. Every sin that a man doeth is without the body; but he that committeth fornication sinneth against his own body."
A concise definition of fornication is "sexual intercourse between people not married to each other," including pre-marital and adulterous relations.
Cambridge Dictionary defines fornication as "the action of having sex with someone who you are not married to."
From the King James Dictionary, Fornication is defined as Sexual immorality:
"Be ye therefore followers of God, as dear children; and walk in love, as Christ also hath loved us, and hath given himself for us an offering and a sacrifice to God for a sweetsmelling savor. But FORNICATION, and all uncleanness, or covetousness, let it not be once named among you, as becometh saints; neither filthiness, nor foolish talking, nor jesting, which are not convenient: but rather giving of thanks." (Ephesians 5:1-4)
The following text is from Russell Moore's blog post "Premarital Sex?":
Christians talk a lot about premarital sex. And I think that’s a mistake. I don’t think it’s a mistake because the issue is unimportant but because the grammar is skewed. The word “fornication” is almost gone from contemporary Christian speech. It sounds creepy and antiquated. Instead, we talk about “abstinence” and “premarital sex.”
According to Russell Moore, the loss of the words “fornicate” and “fornication” implicitly cedes the moral imagination to the sexual revolutionaries because the words “fornication” and “premarital sex” aren’t interchangeable. Fornication isn’t merely “premarital.” Premarital is the language of timing, and with it, we infer that this is simply the marital act misfired at the wrong time. But fornication is, both spiritually and typologically, a different sort of action from the marital act. That’s why the consequences are so dire.
Fornication pictures a different reality than the mystery of Christ presented in the one-flesh union of covenantal marriage. It represents a Christ who uses his church without joining her as a covenant and permanently to himself. The man who leads a woman into the sexual union without a covenantal bond is preaching to her, to the world, and to himself a different gospel from the gospel of Jesus Christ. And he is forming a real spiritual union, the Apostle Paul warns, but one with a different spirit than the Spirit of Christ (1 Corinthians 6:15).
This is important because the Scripture makes clear that “fornicators will not inherit the kingdom of God” (1 Cor. 6:9-10; Revelation 21:8). The language of “premarital sex” can enable conscience to evade repentance. After all, if the problem is merely of “timing” or “waiting,” then the problem is resolved once one is married. The event was in the past.
This makes fornication even more dangerous, in this sense, than adultery. Both fornication and adultery are acts of infidelity. But if he is repentant, a man who has committed adultery understands something of how he’s broken trust, and attacked a covenant. He can see that even when his wife forgives him, he must invest years in rebuilding trust. He can understand why his wife concludes that if he’ll cheat with one woman, why would he not cheat with another? He must work to show himself faithful.
The fornicator can be deceived into thinking that marriage has solved the problem. He doesn’t see the ongoing nature of the problem. Often he finds it difficult to lead his wife spiritually or to gain her trust fully. The root problem is a sin committed together, driving the couple apart.
Moreover, she knows that his libido is stronger than his conscience, especially if he professed to be a Christian before the marriage. If he’s able to justify his fornication, he will justify his adultery. They are not two separate things but two different phases of the same thing: immorality in contrast to the self-giving and uniting covenant of marriage.
We ought not to be ashamed of the Christian language of “fornication,” but instead to be ashamed of fornication itself.
That doesn’t make us more censorious. When we speak honestly, we are able to speak with more liberating power to sinners, including sexual sinners, in our streets and sidewalks, and pews. The blood of the cross can cleanse any sin, but no one comes to the cross without repentance. When we speak bluntly and honestly, we lead people to the cross—to repent, not just to rebrand.
(Excerpt from Russell Moore's: Premarital Sex?)
Let marriage be held in honor among all, and let the marriage bed be undefiled, for God will judge the sexually immoral and adulterous. ~ Hebrews 13:4
Flee from sexual immorality. Every other sin a person commits is outside the body, but the sexually immoral person sins against his own body. Or do you not know that your body is a temple of the Holy Spirit within you, whom you have from God? You are not your own, for you were bought with a price. So glorify God in your body. ~ 1 Corinthians 6:18-20
But because of the temptation to sexual immorality, each man should have his own wife and each woman her own husband. ~ 1 Corinthians 7:2
Now the works of the flesh are evident: sexual immorality, impurity, sensuality, idolatry, sorcery, enmity, strife, jealousy, fits of anger, rivalries, dissensions, divisions, envy, drunkenness, orgies, and things like these. I warn you, as I warned you before, that those who do such things will not inherit the kingdom of God. ~ Galatians 5:19-21
And he said, “What comes out of a person is what defiles him. For from within, out of the heart of man, come evil thoughts, sexual immorality, theft, murder, adultery, coveting, wickedness, deceit, sensuality, envy, slander, pride, foolishness. All these evil things come from within, and they defile a person. ~ Mark 7:20-23
You are doing the works your father did.” They said to him, “We were not born of sexual immorality. We have one Father—even God.” Jesus said to them, “If God were your Father, you would love me, for I came from God and I am here. I came not of my own accord, but he sent me. ~ John 8:41-42
Put to death therefore what is earthly in you: sexual immorality, impurity, passion, evil desire, and covetousness, which is idolatry. ~ Colossians 3:5
“God is loving to man, and loving in no small measure. For say not, I have committed fornication and adultery: I have done dreadful things, and not once only, but often: will He forgive? Will He grant pardon? Hear what the Psalmist says: How great is the multitude of Your goodness, O Lord!
Your accumulated offenses surpass not the multitude of God’s mercies: your wounds surpass not the great Physician’s skill. Only give yourself up in faith: tell the Physician your ailment: say thou also, like David: I said, I will confess me my sin unto the Lord: and the same shall be done in your case, which he says immediately: And you forgave the wickedness of my heart” ~ St. Cyril of Jerusalem
"The Devil endeavors by every means to keep men in error, in the enticement of the passions, in darkness of mind and heart; in pride, avarice, covetousness, envy, hatred, wicked impatience and irritation; in evil despondence, in the abominations of fornication, adultery, theft, false witness, blasphemy, negligence, slothfulness, and sluggishness." My Life in Christ ~ St. John of Kronstadt
“It is a fact, brothers and sisters, that the path of the saints in this life is one full of troubles. They either endure the pain of longing for that which is to come, like the one who said, ‘Woe is me that I have such a long pilgrimage’ (Pslam 120:5, LXX) or they are distressed by their longing for the salvation of others, as Paul wrote to the Corinthians, ‘I am afraid that whey I come to you, God may humble me and cause me to weep and mourn over many who have sinned and not repented of impurity, fornication and licentiousness which they have practiced.'” ~ St. Athanasius
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