Traditional dictionary definitions of fornication and adultery generally define fornication as sexual relationships between unmarried people and adultery as a sexual relationship between two people in which at least one of the people involved is married to someone else.
Is there a difference between fornication and adultery?
In the King James and New King James Versions of the Bible, fornication is a word used in the Old Testament in relation to sexual sins. It is also used to talk about idolatry. For example, in 2 Chronicles 21, the fornication or sexual immorality of the people included involvement in idolatry with Baal. In Ezekiel 16, fornication was repeatedly used to describe the idolatry of God's people. In the New Testament, fornication is often the translation of the Greek word porneia that includes sexual immorality of many kinds, both adultery and other sexual sins. In Matthew 19:9, this word, translated "sexual immorality," is used as a case in which God permits divorce.
In the Bible, adultery is used in the normal sense as sexual relations outside of a person's marriage. While the Bible also uses the word figuratively to speak of the "spiritual adultery" of God's people, adultery is typically used in reference to an extramarital relationship. Mentioned 22 times in the New Testament, it is used only once in reference to spiritual adultery (Revelation 2:22). All other times it is mentioned in its normal sense as a sinful practice.
Adultery is also specifically listed as prohibited in one of the Ten Commandments (Exodus 20). This made it a practice especially condemned in Jewish culture. Most notable was the affair of King David with Bathsheba that caused much trouble. Yet even in this case, David later repented and received forgiveness from God, despite the consequences (Psalm 51). Likewise, John 7:53-8:11 describes a woman caught in adultery whom Jesus forgives.
In the New Testament, adultery is likewise condemned. It serves as one of the only reasons given that provide opportunity for divorce (though not required). Jesus mentioned this is Matthew 5:32 and 19:9. James 2:11 noted both adultery and murder as sin before God.
Both fornication and adultery are considered sinful in Scripture. However, the Bible is also clear that God provides forgiveness for these sins, and offers new life to those who will trust in Him.
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