Why is sex outside the context of marital intimacy evil?
We are in Christ. Christ is in us. This is a union we cannot truly comprehend. But the reality is obvious: we now belong to him. “You are not your own,” Paul says, “for you were bought with a price” (1 Cor. 6:19-20). The price God paid for us so that we may no longer belong to sin but to him as our new master is the very blood of his Son Jesus. Like in marriage, everything the husband owns, the wife also owns when they got married.
Because of this reality, Paul said that sex with a prostitute or someone other than your spouse is not just a physical act with physical implications (like getting STDs). It is also a spiritual act with spiritual ramifications. Sex is a reflection of the desire of God for an intimate relationship with us. God created marriage and sexual intimacy only in marriage to reflect that reality. The two shall become one flesh – that’s God’s intent in creating marriage.
When we pay for the services of a prostitute, we treat the payment of Christ’s blood for us as cheap. When we offer our body for a price to be used by others, we give to others what rightfully belongs to our spouse (or future spouse) alone. It is like saying that we can be united with Christ and indulge in sexual pleasures outside of marriage at the same time. That’s why Paul disagrees very strongly, “Never!” Our body belongs only to Jesus (and our spouse as a reflection of that intimate union with him) and to no one else.
We are now the temple of the Holy Spirit (v. 19). Here’s another present reality that we need to remember to help us in our battle with sin, particularly in this passage the sin of sexual immorality. Our body is God’s temple. The temple is where God’s glory dwells. The temple only contains holy or consecrated things. So, in the same way, every use of our body must be fully consecrated to God alone. It must not be used for any other purpose. That is why he is called the Holy Spirit. To indulge our eyes, our bodies, and our minds with lust and other sensual pleasures apart from the marriage bed is to fight against the Holy Spirit.
Our body is a temple. It is a place of worship. Our hands are for worship, not for masturbation. Our eyes are for gazing at God’s glory, not at nude women. Our strength is for the service of God, not to serve our own lusts or the lusts of others.
We are God’s temple. The very presence of God is here within us. Think about that the next time you are tempted to have sex with your boyfriend. Your body is God’s. No man apart from your husband has any right to own that and use for his own purpose. Every part of our body must be tattooed with this: “Reserved only for God and his purposes.”