Fornication in the Bible: Key Verses from the King James Version

Which Bible verses mention fornication?

The word “fornication” appears in the King James Version (KJV) New Testament wherever the translators met the Greek noun porneia: 26 times, spread over 25 verses, from the Gospel of Matthew to the Book of Revelation ^[1]. Every one of those occurrences is rendered “fornication” or, in two lists of vices, “fornications” ^[1].

The Gospels use the word in three settings. In Matthew 5:32, Jesus says that a man who puts away his wife, “saving for the cause of fornication,” causes her to commit adultery, and Matthew 19:9 repeats the exception ^{[2] [1]}. In Matthew 15:19 and Mark 7:21, “fornications” appears in a list of evils that come out of the heart; John 8:41 also uses it ^[1].

The Book of Acts uses it three times. When the apostles and elders settled what Gentile converts had to observe, their letter asked them to keep away from food offered to idols, from blood, from strangled animals “and from fornication” (Acts 15:29); the word also appears in Acts 15:20 and 21:25 ^{[3] [1]}.

Paul’s letters supply most of the remaining verses: Romans 1:29, 1 Corinthians 5:1, 6:13, 6:18 and 7:2, 2 Corinthians 12:21, Galatians 5:19, Ephesians 5:3, Colossians 3:5 and 1 Thessalonians 4:3 ^[1]. Revelation then uses the word repeatedly, mostly in a figurative sense ^[1]. Related words widen the picture: the Greek pornos is translated “fornicator” five times and “whoremonger” five times, including Hebrews 13:4, which reads “whoremongers and adulterers God will judge” ^{[4] [5]}. The table below gathers the verses most often cited.

Key King James Version verses on fornication

Reference	KJV key words	Greek term	Context
Matthew 5:32	“saving for the cause of fornication”	porneia	Jesus’ teaching on divorce
Acts 15:29	“and from fornication”	porneia	Letter of the apostles and elders to Gentile believers
1 Corinthians 6:18	“Flee fornication”	porneia (noun) and a related verb	The believer’s body as a temple of the Holy Spirit
1 Corinthians 7:2	“to avoid fornication”	porneia	Marriage presented as a safeguard
Galatians 5:19	“Adultery, fornication, uncleanness”	porneia	List of the works of the flesh
1 Thessalonians 4:3	“abstain from fornication”	porneia	Sanctification presented as God’s will
Hebrews 13:4	“whoremongers and adulterers God will judge”	pornos	Marriage to be held in honor by all
Revelation 14:8; 17:4; 18:3	fornication (figurative)	porneia	Metaphor for idolatry

What did Paul mean by “flee fornication”?

Paul’s instruction is to avoid sexual sin altogether, and he justifies it by calling it a sin committed against one’s own body. The verse opens with “Flee fornication” and goes on to contrast every other sin, which a person commits outside the body, with fornication, which is committed against the sinner’s own body (1 Corinthians 6:18) ^[6].

The surrounding verses give his reasons. Believers’ bodies belong to Christ as his members and should not be joined to a prostitute (6:15–16); the body is a temple of the Holy Ghost; and Christians have been bought at a price, so they should glorify God in body and spirit (6:19–20) ^[6]. In the second half of verse 18 the KJV switches to a verb, “committeth fornication,” which renders a Greek verb related to porneia ^[1].

Chapter 7 turns to marriage. Answering questions the Corinthians had sent him, Paul writes that “to avoid fornication,” every man should have his own wife and every woman her own husband, and that husband and wife owe each other their marital duties (7:2–3) ^[7]. The footnotes of the New American Bible Revised Edition (NABRE), the Catholic translation published by the U.S. bishops, explain the phrase about sinning against one’s own body as a sign of how deeply sexual disorder runs against the body’s purpose ^[8]. A closer reading of the passage is offered in our article on 1 Corinthians 6:18 in context.

The passage itself sets out a principle, not a code of conduct. It says nothing about engagement, dating or living arrangements; the practical rules that American churches draw from it, such as pledges to wait until marriage, came much later and vary from one tradition to another.

What does the Greek word porneia cover?

Porneia covers a wider field than the modern English word “fornication.” The Blue Letter Bible lexicon defines it as illicit sexual intercourse in general, listing adultery, homosexual acts, bestiality and intercourse with close relatives (as in Leviticus 18) among its uses ^[1]. It also lists a metaphorical sense, the worship of idols, which explains its frequent use in Revelation ^[1].

The English word has its own history. “Fornication” entered English around 1300 from Old French fornicacion and Late Latin fornicatio, built on fornix, a Latin word for an arch or vaulted chamber that came to mean a brothel ^[9]. In strict usage it meant consensual sex between two unmarried people, but in biblical usage its meaning was extended to include adultery ^[9].

Scholars still debate how far the Greek term reaches. The New Testament scholar Bruce Malina argued that the Bible, the Torah in particular, did not forbid consensual, non-commercial sex between partners who were neither married nor engaged to someone else ^[10]. A July 2024 article in the South African journal In die Skriflig, by Benno A. Zuiddam, rejects that reading on philological grounds and concludes that Hebrew and Greek texts, and the rabbinic and apostolic traditions after them, treat sex outside an established marriage as a sin with several dimensions ^[10]. Zuiddam describes Malina’s approach as a liberal reading that assigns meaning to the text rather than drawing it out ^[10].

The divorce clause in Matthew 5:32 shows how much the reading matters. Because it concerns married people, readers who follow the lexicon take porneia there to include adultery ^[1]. The Catholic NABRE translates the clause as “unless the marriage is unlawful,” and its footnote links porneia to unions between close relatives forbidden by Leviticus 18, the same concern found in Acts 15 ^[11]. On that reading, the clause is not a true exception to the ban on divorce when a marriage is lawful ^[11].

Why does the KJV say fornication when newer Bibles say sexual immorality?

The KJV says “fornication” because its translators, working in early seventeenth-century England, chose one English word for porneia and kept it throughout the New Testament ^[1]. Published in 1611 under King James I and also known as the Authorized Version, it was generally accepted as the standard English Bible from the mid-seventeenth to the early twentieth century ^[12].

Many modern translations prefer a broader phrase. The New International Version opens 1 Corinthians 6:18 with “Flee from sexual immorality” ^[13], and the Catholic NABRE writes “Avoid immorality” ^[8]. The NABRE still keeps “fornicators” in the vice list of 1 Corinthians 6:9, a sign that translators weigh each context separately ^[8].

The change follows the way English vocabulary moved. Because English “fornication” came to mean sex between unmarried people ^[9], while porneia also covers adultery, incest and other acts ^[1], a phrase such as “sexual immorality” stays closer to the breadth of the Greek. Readers and churches that still use the KJV keep the older word. The shift in vocabulary is traced in our article on why modern Bibles say “sexual immorality”.

How do Catholics, Protestants and Latter-day Saints read these verses?

Catholic, Latter-day Saint and Southern Baptist teaching all read these verses as reserving sex for marriage, while some mainline Protestant bodies use more open wording. The Catechism of the Catholic Church gives the most precise definition: fornication is “carnal union between an unmarried man and an unmarried woman,” and it is described as gravely contrary to the dignity of persons and of human sexuality (paragraph 2353) ^[14].

The Church of Jesus Christ of Latter-day Saints frames the same verses as part of its law of chastity. Its Gospel Topics entry defines chastity as “not having any sexual relations outside of a legal marriage” between a man and a woman, and cites 1 Thessalonians 4:3, which in the KJV reads “abstain from fornication” ^{[15] [16]}. The same entry adds that people who have been sexually abused have not broken the law of chastity and have nothing to repent of ^[15].

Protestant churches show more variety. The Southern Baptist Convention’s confession, the Baptist Faith and Message 2000, says Christians should oppose “all forms of sexual immorality,” naming adultery, homosexuality and pornography, and describes marriage as the channel of sexual expression according to biblical standards ^[17]. The Evangelical Lutheran Church in America (ELCA), a mainline body, states in its social statement on sexuality that it opposes promiscuous or casual sexual relationships and does not favor cohabitation outside marriage, while asking that the greatest sexual intimacies be matched by the highest level of commitment, such as is found in marriage ^[18].

Outside these official texts, some scholars follow arguments like Malina’s and read porneia as a narrower set of forbidden relationships rather than every sexual act outside marriage. Their critics, such as Zuiddam, answer that the Hebrew and Greek vocabulary condemns sex without an established marriage ^[10].

Does the Bible treat fornication as worse than other sins?

The Bible singles fornication out in one respect but also places it among many other sins, and churches weigh these texts differently. Paul’s contrast between sins committed outside the body and fornication, committed against one’s own body, sets it apart ^[6]. Yet Galatians 5:19–21 lists fornication next to idolatry, hatred, wrath, envy and drunkenness, and warns that all who practice such things will not inherit the kingdom of God ^[19].

The Catechism distinguishes degrees of gravity among sins. The Catechism says mortal sin requires grave matter, full knowledge and deliberate consent, notes that some sins are graver than others (murder is graver than theft), and leaves the judgment of persons to God’s justice and mercy (paragraphs 1857–1861) ^[20]. Fornication counts as grave matter, but personal guilt depends on those conditions.

Latter-day Saint scripture goes further. In the Book of Mormon, the prophet Alma tells his son Corianton that sexual sin is “most abominable above all sins save it be the shedding of innocent blood” or denying the Holy Ghost (Alma 39:5) ^[21]. Protestant confessions such as the Baptist Faith and Message do not rank sexual sins against other sins; they list sexual immorality among the evils Christians should oppose ^[17].

All of these traditions also teach that the sin can be forgiven. Catholic canon law describes the sacrament of penance as the means by which the faithful who confess with sorrow receive God’s forgiveness ^[22], and the Latter-day Saint guidance says the Lord fully forgives those who repent ^[15]. Hebrews 13:4 pairs that hope with a warning: marriage is to be honored by all, while “whoremongers and adulterers God will judge” ^[5].

Frequently asked questions

How many times does fornication appear in the KJV?

The noun “fornication” translates the Greek porneia 26 times in the KJV New Testament, in 25 verses, according to the Blue Letter Bible concordance ^[1]. The total is higher if you add related words: pornos is rendered “fornicator” five times and “whoremonger” five times ^[4], and a related verb gives phrases such as “committeth fornication” ^[1].

Is fornication the same as adultery in the Bible?

Not exactly. Galatians 5:19 lists adultery and fornication as two separate works of the flesh ^[19], and modern Catholic teaching reserves “fornication” for sex between two unmarried people ^[14]. The Greek porneia is broader, however, and its lexicon definition includes adultery among illicit sexual acts ^[1].

Does the Bible define fornication?

No. No verse gives a formal definition; the meaning comes from how the words are used and from lexicons, which describe porneia as illicit sexual intercourse in general ^[1]. Precise definitions come from churches, such as paragraph 2353 of the Catholic Catechism ^[14].

Is fornication forgivable in Christian teaching?

Yes. Catholic teaching offers forgiveness through the sacrament of penance ^[22] and entrusts the final judgment of persons to God’s mercy ^[20]. The Church of Jesus Christ of Latter-day Saints teaches that the Lord fully forgives those who repent, with confession to a bishop for serious sins ^[15].

What is a whoremonger in the King James Bible?

A whoremonger, in KJV English, is a man who engages in unlawful sexual relations. The word translates the Greek pornos, which the KJV renders “whoremonger” five times (including Hebrews 13:4 and Revelation 21:8) and “fornicator” five times ^[4]. More on these older terms is in our page on fornicators and whoremongers.

Why do some Bibles say “immorality” instead of “fornication”?

Because modern English “fornication” usually means sex between unmarried people, while the Greek porneia covers a wider range of illicit acts ^{[9] [1]}. Translations such as the NIV (“sexual immorality”) and the Catholic NABRE (“immorality”) choose broader words to match the Greek ^{[13] [8]}.

What did Acts 15 ask Gentile Christians to avoid?

Four things: meat offered to idols, blood, strangled animals and fornication (Acts 15:29) ^[3]. The letter from the apostles and elders said that keeping these rules was enough, placing no heavier burden on Gentile converts ^[3].