How to convince an atheist of no sex outside marriage

CAF members,

I have an atheist friend with whom I have been debating about human sexuality. In a nutshell, my friend claims that sex is a need and that abstinence programs do not work. How should I respond to him in order to try to convince him that sex is best only in marriage? Do you have any statistics to help me prove my point?

Thanks for your help.


Good luck trying to change beliefs in an Athiest! Only through prayer, I believe, will it happen. The change has to come from within.

Contraception and condoms are not 100% reliable in terms of preventing pregnancy and STDs. Why risk getting pregnant or an STD for someone you are not married to? I don’t know how convincing they will find it but it is the reason why I would be inclined to wait even if I was an atheist.

While an argument can be made with an atheist about it being healthier/safer to have fewer partners and reserve sex for longterm partners, I don’t know that there’s a good (non-theological) argument for waiting for marriage.

Your friend is incorrect. Food, water and sleep are needs,
sex is a want. People do not die if they don’t have sex.

Ditto. I would ask why exactly it is this friend of the OP thinks sex is a need.

I think you bit off more than you can chew. Atheists don’t want truth they want reassurance of their own beliefs. And their greatest reassurance is when you can’t answer their questions. Nevertheless, your friend is misguided on human nature. Sex is not a need even if it feels that way. A person can live a normal life without ever having sex. Also, to argue that sex is a need opens the door for the argument that rape is acceptable. There are some very good lawyers that can turn that need-for-sex into a courtroom victory.

I would ask your friend why he feels the need to wear clothes and use indoor toilets. Sex is a very natural thing, but so is being naked and shitting in the woods. Excuse my language. Humans are animals and animals do all sorts of “natural” things like fornication, homosexuality, bestiality, pedophilia, and rape. Humans, however, make and wear cloths, build complex homes, make art and music, cook food, play sports, and do many more things that give us a complex society. As humans we should always being trying to be greater than our animal counterparts. From a secular viewpoint, marriage is a defining ritual that sets us apart from other animals. We should strive to make that marriage as unique as possible with monogamy and waiting until marriage for sex.

As for the abstinence programs, nothing is 100%. Well, if you practice abstinence it’s 100% effective, but abstinence programs are not 100% in helping every person. Most critics of these programs expect 100% results and when they don’t get them they use it as an excuse to scrap the whole thing. Of course, contraception is not 100% and yet they have no desire to scrap that. I don’t know the stats for abstinence programs off the top of my head, but let’s say even if abstinence programs are only 10% effective wouldn’t it be worth saving those 10% from STDs and emotional trauma that could accompany premarital sex?

Obviously, we get most of our truth about marriage from God’s teaching on the topic. However, there is a good reason for marriage.

I don’t have the statistics on hand, I will have to look them up (or someone can help me out here), but there are several reasons why sex outside of marriage is bad.

  1. The impact on children:
    No birth control is 100%. So, either the couple in question will wind up killing innocent babies (abortion) or having children outside of wedlock. Now, there are some who are lucky enough never to be in that situation, but, let’s face it, the staggering number of abortions we have right now is proof that birth control doesn’t work.

So, when kids wind up entering the equation, the statistics show that those children who have married parents fair far better than parents who are cohabiting. There is more stability for them, and they end up doing better in school, social life, etc. etc.

  1. The impact on the couple
    The statistics also show that couples who have sex outside of marriage are more likely to get divorces, be unhappy in their marriage, and are more likely to have affairs.

This leads back to the children as well. Statistics show that children who grow up in single parent homes (particularly without their dad) are more likely to end up in jail, do drugs, etc. etc.

Again, I am sorry that I don’t have those stats on hand. I will look for them and try to post them. However, I promise I am not making that up. God has a good reason for the things he teaches, and his plan is the best way. But even if you don’t believe in God, you can still see the good reasons for why you should follow these teachings. Especially the teachings on marriage.

Marriage is essential to our world. Marriage is the cornerstone of our society. If the marriage falls apart, the family falls apart. When the family falls apart, our communities fall apart. When communities fall apart, there goes our world. We have to understand the importance of marriage, for the couple involved, the children involved, and the world.

Here are some of the stats regarding my previous post:

Some answers from the Social Sciences:

Children raised in intact married families:
are more likely to attend college
are physically and emotionally healthier
are less likely to be physically or sexually abused
are less likely to use drugs or alcohol and to commit delinquent behaviors
have a decreased risk of divorcing when they get married
are less likely to become pregnant/impregnate someone as a teenager
Children receive gender specific support from having a mother and a father. Research shows that particular roles of mothers (e.g., to nurture) and fathers (e.g., to discipline), as well as complex biologically rooted interactions, are important for the development of boys and girls (Marriage and the Public Good: Ten Principles, 2006).
A child living with a single mother is 14 times more likely to suffer serious physical abuse than is a child living with married biological parents. A child whose mother cohabits with a man other than the childís father is 33 times more likely to suffer serious physical child abuse (The Positive Effects of Marriage: A Book of Charts, Patrick Fagan).
In married families, about one- third of adolescents are sexually active. For teenagers in stepfamilies, cohabiting households, divorced families, and those with single unwed parents, the percentage rises above one-half (The Positive Effects of Marriage: A Book of Charts, Patrick Fagan).
Children of divorce experience lasting tension as a result of the increasing differences in their parents values and ideas. At a young age they must make mature decisions regarding their beliefs and values. Children of so- called “good divorces” fare worse emotionally than children who grew up in an unhappy but “low-conflict” marriage (Ten Findings from a National Study on the Moral and Spiritual Lives of Children of Divorce, Elizabeth Marquardt).

There is this study about how couples who wait have better sex…and who doesn’t want that :wink:

And here is a really good article with several of the points I made about premarital sex, and a few others, particulalry

Decreased ability to bond and corresponding decreased marital stability

Well once upon a time the answer might be to jail people who have sex outside of marriage, but I’m not sure how effective that would be and SCOTUS would strike it down as unconstitutional anyhow.


You have stated that sex is best only in marriage. That’s a personal opinion. if you wanted to show that most people thought that way, then you’d need to access a poll that asked that specific question: ‘Is sex best only in marriage’.

To be honest, the answer would probably be no. That a minority believed it.

If you want to show him that sex outside marriage can cause problems (stds, unwanted pregnancy etc) then there are stats that will show that problems CAN occur. But not WILL occur.

So maybe he is correct. As far as he is concerned, it’s better and because he knows his partner very well, there is no chance of an std. And maybe he has had a snip so they can’t get pregnant.

At which point, you should be honest enough to say: ‘Fair enough, I appear to be wrong in your particular case’.

In my experience you cant. Our faith guides us to the level and extent of our morality.

In my conversations with people, usual retorts to me are

‘Thats old fashioned’ , ’ people live together nowdays’
List goes on.

People who state sex is a need have not developed self discipline. And are quite selfish to believe another should be obligated to fulfill their need. Thats where things like fasting help us to develop discipline.

Gotta “love” these unsubstantiated and very derogatory utterances. Shame on you!

Many people fail to use birth control correctly or if they are comfortable enough with their partner they won’t use it altogether. Sex complicates relationships. I think it can be easier to leave a relationship when no sexual attachment is formed.

Ask him if he would take his smartphone in the shower with him. If he’s sensible he’ll say no. Ask him why. Then tell him that you wouldn’t do it because you know it’s not how the manufacturer intended it to be used. You know it’s not what’s best for the phone. It’s the same with sex. God created sex, and therefore He knows that it is best in a lifelong marriage between a husband and wife when it is open to life.

Not sure this works without a belief in God.

Also, based on casual observation a large portion of marriages end I divorce. Depending on which stats that is around 40% (and declining).

Theology aside, no sex before marriage can work well for those who marry by their mid 20s, but I’d imagine it adds significant pressure to marry, even if something is amiss.

You realize, don’t you, that the exact same argument can be made about those who believe in God…that believers are not open to anything that does not validate their already-held beliefs. They just want reassurance that their beliefs are true.

Regarding sex outside of marriage, one can make some good arguments that sex outside of marriage can be detrimental to the order of our society and to the welfare of any resulting children. But without making it a religious argument, I don’t see how you can say that sex outside of marriage is objectively “bad.”

Agreed. An argument that relies on the existence of God is not going to resonate with someone who does not believe in God.

From a pragmatic standpoint you could tell your friend that married people on average have more sex than single people or people with non-married lovers. The reason is that you don’t need to go looking for a hook-up; there’s already somebody living in your house to do that with. Additionally it is safer (no risk of STDs if monogamous, and less risk of the relationship ending as both are more heavily invested in it) and less expensive (both people are pooling their income and Natural Family Planning, unlike contraceptives, is free).

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