Sex before marriage with spouse?

After having a conversation with a few friends today, we came across a topic that no one had a solid answer on. If you have premarital sex with someone and end up getting married to them, is it still a sin?

Seeing as sex before marriage is an act of adultery against your future spouse, but you committed that act with your spouse… are you in the wrong?

Just looking for any opinions on this!


Elaborate please?

The sinfulness of an act is independent of future acts. As such, there is no moral difference between having sex with a future spouse and having sex with someone else.

It is a sin still. It breaks laws given to us for our own good.

Think of speeding. Laws regarding speeding are in place for people’s protection, because excess speed is a major cause of road accidents and especially fatalities. A person does the wrong thing when they speed, because they disregard this risk. If they speed around everywhere and happen not to kill or injure anyone, they have still done the wrong thing.

When people have sex before marriage, they also take on a risk of harm. Not all engagements (let alone other types of relationships) result in marriage, and when they don’t marry the premarital sex harms the two people and their future spouses. When people have premarital sex and happen to get married, they are like the speeding driver who happens not to kill anyone on the road. They’ve done the wrong thing; it just happens to have worked out for them.

It is fornication not adultery. Fornication is a sin.

The sex hormones have a powerful attractive effect. They bind people emotionally.

In marriage that is a good thing. The couple (presumably) chose each other through a rational thought process, and made a lasting commitment to support each other. The hormones reinforce the marriage bond and give the couple an added reason to remain together even when the stresses of everyday life would pull them apart.

Outside of marriage it is not such a good thing. An unmarried couple has seldom worked through the phase of determining whether they belong together long-term, and certainly hasn’t made a lasting commitment to face life together. Yet the sex hormones still bind them emotionally, even when they are completely wrong for each other.

Having premarital sex then getting married to someone because the sex hormones override your common sense is the worst mistake any couple can make. That is why premarital sex is a sin.

it would be the sin of fornication

Sex outside of marriage is a mortal sin. That means both have commited a serious sin which can send them to Hell forever! That sin remains on their soul until they confess it. Sex is NOT a loving act when it damns some one to Hell forever.

Our virginity, and sexuality are a great gift, which God wisely instructs us to share only with our life long spouse. God ordained sex to be expressed only in marriage to unify a couple, and so they could bring up their children in a committed family. :thumbsup:

Sex is NOT a loving act when it damns some one to Hell forever.

INDEED! Not to mention both individuals MUST attend confession before the sacrament of marriage [which I hope they were planning to do anyway …]…
Plans to marry or not, it is still a BIG “no-no” :dts:

It is best for unmarried couples to avoid placing themselves in situations where the potential for such temptations may arise… [MOST ESPECIALLY NOT CO-HABITATING before marriage.]

-just my :twocents:

At the risk of diluting your message, I’m going to quibble with you:

Fornication is grave matter. As a result, fornication might be a mortal sin. However, if it is done without full knowledge (of its sinfulness) or complete consent, it is a venial sin. :wink:

Yes (except he part about adultery --for it is fornication not adultery)

and it is not an opinion but a certainty. Such is objectively the grave sin of fornication.

Objectively fornication is a mortal sin. A grave matter.

It might subjectively have been a venial sin in a singular case …due to say invincible ignorance etc


One of the reason is …

… there is no way to warranty that you will definitely marry this person (there is always a chance that you will break up before marriage)

Reminds me of the story of two Anglican bishops discussing this topic. One was saying to the other “Well I can tell you that I didn’t have sex with my wife before we were married - what about you?” The other thought for a moment and then said “I don’t know - what was her name?”


I do not believe that there is any requirement that one MUST attend confession before the sacrament of marriage. While it’s certainly a good idea, I’m almost positive that it’s not mandatory. It was never brought up during my Pre-Cana classes.

Yes, it is a grave sin against the sixth commandment.

Not sure where you got this idea. It is not Catholic teaching.

Fornication is wrong because it is a misuse of our sexual faculties and an offense against God. It has nothing to do with “adultery against a future spouse”.=

We approach the sacraments worthily only when in a state of grace.

Can.* 1065 §1. Catholics who have not yet received the sacrament of confirmation are to receive it before they are admitted to marriage if it can be done without grave inconvenience.

§2. To receive the sacrament of marriage fruitfully, spouses are urged especially to approach the sacraments of penance and of the Most Holy Eucharist.

But just to clarify (because you know people are going to misunderstand and freak out), being in a state of mortal sin is bad, but it does NOT render the marriage invalid.

In Christ,

The OP is right to try to reason beyond mere rules and slogans to the principles that underly them. That’s an excellent practice.

Obviously fornication is a grave sin. But WHY is it a grave sin? By definition, sins are things that reduce our capacity to give and receive love. On the larger scheme of things, a major that fornication is wrong is because it dilutes the precious and unique bond that God intended for a husband and wife to share only with one another. It weakens the effect and subsequently God’s design for the marriage bond.

So doesn’t that support the OP’s supposition that premarital sex between two people that later marry is really no big deal?

No. You simply AREN’T married until you are. If you are intimate with someone to whom you have not been joined together by God, then you are saying with your ACTIONS “I am willing to have sex with someone not my spouse.” Wiggle all you want about intentions, the fact remains that right now, she is NOT your spouse. That message remains and festers, even if you do marry. Plus, intentions change, surprises happen, minds change. You aren’t married until you are. Jumping the gun will gravely wound you.

If you’re THAT sure you’re going to get married, just go ahead and GET married. If there are real reasons not to yet, then there are real reasons NOT to yet! Telling the truth with the rest of your body is as important as telling the truth with your tongue.

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