Did I commit a deadly sin by having sex with my girlfriend, even though I know I’m going to marry her?

Answer:

You've only been serious about this girl for a little over three months, yet you are already having sex with her -- despite a commitment to wait until marriage for sex. I hope she is wondering how long it will take you to commit adultery after you are married. So far you haven't demonstrated strong reliability in your life.

"Do you not know that the unrighteous will not inherit the kingdom of God? Do not be deceived. Neither fornicators, nor idolaters, nor adulterers, nor homosexuals, nor sodomites, nor thieves, nor covetous, nor drunkards, nor revilers, nor extortioners will inherit the kingdom of God" (I Corinthians 6:9-10).

God doesn't rate sin as we do. All sin that is left unrepented of will lead to your spiritual death and ultimately eternal death. "For the wages of sin is death" (Romans 6:23). You committed fornication with your girlfriend when you put your penis where it didn't belong. It can be forgiven, but what truly bothers me is your attempt to justify your sin. You claim it wasn't lust but love.

Lust is a very strong desire, usually for something that is unlawful. The reason you dropped your pants was that you had a very strong desire to have sex. But because the two of you were not married that desire was for something that was not lawful for you to have. "Now concerning the things of which you wrote to me: It is good for a man not to touch a woman" (I Corinthians 7:1). You are trying to sugarcoat the fact that you were thinking with what is between your legs instead of your head. You were acting no better than an animal in heat.

Paul defined love this way:

"Love suffers long and is kind; love does not envy; love does not parade itself, is not puffed up; does not behave rudely, does not seek its own, is not provoked, thinks no evil; does not rejoice in iniquity, but rejoices in the truth; bears all things, believes all things, hopes all things, endures all things. Love never fails" (I Corinthians 13:4-8).

Is it kind to your girlfriend to risk getting her pregnant? Was putting your penis in her polite behavior? Was the fact that you used her for your sexual gratification "not seeking its own?" As the days led up to your fornication were you thinking no evil in regards to her? Can you claim that though you sinned and led another person into sin while claiming it was "love" that you are not rejoicing in iniquity (sin)?

My point is that what the two of you did is not love. It was a selfish sexual gratification. You didn't do it for the other person, you did it for yourself.

You state that you know you are going to marry this girl. I suspect that despite your certainty you haven't given her a ring and you haven't set a date -- the relationship is too new. You might be right that you will eventually marry her, but the truth is that the future is not in our control. For all I know you might be hit by a bus tomorrow. "Come now, you who say, "Today or tomorrow we will go to such and such a city, spend a year there, buy and sell, and make a profit"; whereas you do not know what will happen tomorrow. For what is your life? It is even a vapor that appears for a little time and then vanishes away. Instead you ought to say, "If the Lord wills, we shall live and do this or that." But now you boast in your arrogance. All such boasting is evil" (James 4:13-16).

God requires that you wait until marriage for sex. He does so for very good reasons. The command is neither arbitrary nor cruel. I would ask that you read "Waiting for the Proper Time" and "Why Sex Outside of Marriage is Wrong" for more details. You need to make your life right with God and give up this sin. Marry this girl first if that is your heart's desire, then you can enjoy a sexual relationship.