You are correct when you say that the Bible teaches sex is for marriage.   After the creation of Adam and Eve, God instituted the marriage arrangement.  Genesis2:24 states “For this reason a man will leave his father and mother and be united to his wife, and they will become one flesh.”  For Adam and Eve, a physical, intimate relationship was one of the blessings of their marriage commitment. God determined this would be the BEST arrangement for the physical and emotional well-being of his entire human family. 

Hebrews 13:4 states that “marriage should be honored by all, and faithfulness should be respected, for God will judge the adulterer and all the sexually immoral.”   

“It is God’s will that you should be sanctified: that you should avoid sexual immorality; that each of you should learn to control his own body in a way that is holy and honorable, not in passionate lust like the heathen, who do not know God; and that in this matter no one should wrong his brother or take advantage of him (or her!).   The Lord will punish men for all such sins…For God did not call us to be impure, but to live a holy life.  Therefore, he who rejects this instruction does not reject man but God…”  (I Thessalonians 4:3-5)

The apostle Paul is perfectly clear in his counsel that all sexual activity outside of the bonds of marriage is immoral and sinful.  God created sex for procreation and pleasure, and as an expression of love between a husband and wife.  Sexual experience must be limited to the marriage relationship to avoid hurting ourselves, our relationship with God, and our relationships with others.

To those who struggle with this temptation, they should realize that pre-marital sex is, in reality, extremely self-centered.  Those who seek immediate physical pleasure do so at the expense of God’s design for themselves and for their partner.  It is reasonable to assume that those who practice premarital sex on an ongoing basis are also deliberately reserving the right to exit the relationship easily, should they decide to – with a “no strings attached” attitude!  This pattern of thinking can only prove detrimental in the long run when seeking to develop a meaningful, lifelong relationship.

 God does not look favorably upon any behavior that He considers sinful, therefore God does not honor or condone the behavior of any couple who is engaging in premarital relations.  Should a Christian couple repent and refrain from all sexual activity up until the time they marry, God would, through the blood of Christ, forgive them in his great mercy and kindness. “If we confess our sins, he is faithful and just and will forgive us our sins and purify us from all unrighteousness.” (I John 1:9)

  Doing what is right in God’s eyes will ALWAYS bring a blessing –The blessing of knowing we are pleasing God, of  keeping our consciences clear before Him, and of setting a good example to those around us.