This is a pretty popular question that comes up with believers and non-believers. I asked the same question myself years ago and luckily was pointed to the Bible for answers. Sometimes it’s difficult to answer something like this and I think it takes a little more discussion than just answering this one question. In my experience, it typically involves a similar question that goes something like “How far is too far?” or “When does sin actually become sin?”
In any case, let’s look and see what Scripture says about this. Let’s see how God defines marriage and why it would be wrong to live together before getting married.
The Bible describes marriage as a committed relationship between one man and one woman that is sanctioned and blessed by God (Genesis 2:22-24). Furthermore, God instituted marriage to be between two people, a male and a female. Jesus added that it is to be permanent (Mark 10:7-9 – ‘Therefore a man shall leave his father and mother and hold fast to his wife, and the two shall become one flesh.’ So they are no longer two but one flesh. What therefore God has joined together, let not man separate).
The divine institution of marriage suggests a covenant among the man, the woman, and God. The marital relationship is more important than any other relationship except one’s relationship with God. It is modeled after God’s relationship with His people, the Church. Jesus is the bride-groom, and the Church is His bride. The unique, committed setting of marriage is also the place God designed for the expression of sex. In 1 Corinthians 6:15-18 (Do you not know that your bodies are members of Christ? Shall I then take the members of Christ and make them members of a prostitute? Never! Or do you not know that he who is joined to a prostitute becomes one body with her? For, as it is written, “The two will become one flesh.” But he who is joined to the Lord becomes one spirit with him. Flee from sexual immorality. Every other sin a person commits is outside the body, but the sexually immoral person sins against his own body), Paul discusses the sinfulness of all sexual relations outside of marriage. In addition to outward sinfulness, sexual sin is a sin against one’s own body. This makes sexual sin uniquely destructive, a clear reason to follow God’s plan for sex.
When it comes to living together before marriage, you may think you are fine just because you are “living together” and nothing more, but I would suggest that you are not. In the midst of living together, you are also opening the door to even more temptation between you two, and hurting any testimony you may have of following Christ as you proclaim that it is a God glorifying thing to live together before marriage. You are also in danger of leading others down a similar path towards sin because of your example (Romans 14:13-22).
Living together before marriage doesn’t reflect the commitment that God instituted and ordained. The good news is that it is never too late to make a change. God forgives sin. That’s what He’s all about. He wants to have a relationship with us, and no situation or sin is too great for Him to forgive. If we want His forgiveness, we must stop committing the sinful act (1 John 3:6 – No one who abides in Him keeps on sinning; no one who keeps on sinning has either seen Him or known Him) and ask God for forgiveness. He will be faithful to forgive us (1 John 1:9 – If we confess our sins, He is faithful and just to forgive us our sins and to cleanse us from all unrighteousness).
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