Many Christians understand that sex is the act of love reserved only for married couple, but many choose not to wait until marriage. Many people simply refuse to acknowledge the direct command of the Bible against premarital sex.
1 Corinthians 6:18
Flee from sexual immorality. All other sins a person commits are outside the body, but whoever sins sexually, sins against their own body.
We aren’t told to calmly walk away or to try to confront it, no, we’re told to get the heck out of dodge. This kind of temptation is far too great for us to deal with it on our own. Obey His Word and run from it.
The Greek word porneia is most often translated “sexual immorality” or “fornication” in the New Testament. Some translations consistently render porneia as “fornication” in order to differentiate it from “adultery.” The word “fornication,” in modern English, primarily carries the idea of premarital sex / sex before marriage. However, porneia does not actually refer, explicitly, to premarital sex. It actually refers to sexual perversion in general. Greek literature from the approximate time period as the New Testament used porneia to refer to prostitution, homosexuality, adultery, incest, and other sexual perversions. So, we should not necessarily read “premarital sex” into every occurrence of porneia in the New Testament. The question arises, then, is premarital sex considered a sexual perversion within the scope of porneia?
In order to determine whether premarital sex is considered a sexual perversion, it is helpful to focus on what sex is supposed to be. The best way to recognize a counterfeit is to be familiar with the truth. Sex, biblically speaking, is intended to be a physical union between a husband and his wife with the goal of reproduction, and/or physical pleasure, and/or emotional closeness. Biblically speaking, though, the determining factor in whether sex is sinful is the question “with whom?”, not “why?” Nowhere does the Bible speak against sex between a husband and his wife. Everywhere sex outside of marriage is mentioned, the Bible condemns it. Sex outside of marriage is a perversion. It does not matter when, with whom, or why; sex between anyone other than a husband and his wife is a perversion of sex. Therefore, premarital sex is a perversion, and condemned every time the Bible condemns porneia.
There is also a more explicitly biblical basis on which to declare premarital sex as porneia. First Corinthians 7:2 reads, “But because of the temptation to sexual immorality (porneia), each man should have his own wife and each woman her own husband.” In this verse, the Apostle Paul presents a problem “the temptation to sexual immorality” and a solution “each man having his own wife and each women her own husband.” If marriage is the solution, the problem logically must be extra-marital. To define porneia in 1 Corinthians 7:2 as prostitution or incest or some other sexual perversion does not make sense if premarital sex is not also a perversion. If premarital sex is not a sin, why is prostitution a sin? Both involve consenting adults. It is biblically clear that marriage is the sanctifying factor in sex. Sex in marriage is good and right. Sex outside of and/or before marriage is a sinful perversion.
The Bible is so abundantly clear about premarital sex that, ultimately, if anyone argues for premarital sex being allowed, it must be due to that person’s desire to engage in premarital sex. Almost any behavior can be justified by a person who refuses to submit to what the Bible says. But, we are never to interpret the Bible based on our wants and desires. Rather, we are to allow the Bible to shape our wants and desires. The biblical message on premarital sex is clear. Premarital sex is a perversion of God’s intention for sex, and is therefore condemned whenever the Bible condemns sexual immorality (Acts 15:20; 1 Corinthians 5:1; 1 Corinthians 6:13, 1 Corinthians 18; 1 Corinthians 7:2; 1 Corinthians 10:8; 2 Corinthians 12:21; Galatians 5:19; Ephesians 5:3; Colossians 3:5; 1 Thessalonians 4:3; Hebrews 13:4; Jude 7).