What Is Infidelity? A Christian Perspective on Faithfulness

What is infidelity? Have you ever wondered what counts as infidelity in marriage? Is cheating limited to sexual unfaithfulness, or can it be defined in broader terms to include things like pornography, flirtations, or the increasingly common “emotional affair”?

Views on this important issue are diverse and hotly contested. Try an internet search on the topic and you’ll end up with more questions than answers, as the consensus in popular culture seems to be: “It depends.”

In other words, according to popular culture the definition of infidelity changes based on how you choose to define the relationship, what you personally believe, how you were raised, and what your values and preferences are. This reflects a general shift toward postmodern thinking about morality within western culture, at least on the popular level. As a Christian Marriage and Family Therapist, I see major problems with this approach.

Different People, Different Perspectives

I know from years of experience working with couples that most romantic relationships are made up of two individuals with radically different opinions, beliefs, backgrounds, and values. This means that the two of you are never completely aligned in how you interpret life and the world around you. If you don’t have an external, fixed point of reference that you both choose to align yourself with, you will find that you are rarely on the same page about anything by default.

Christian marriage addresses this problem with the tradition of wedding vows, promises of unwavering, lifelong devotion and faithfulness expressed in the strongest possible terms (“to have and to hold from this day forward . . . forsaking all others . . . until death do us part”).

These vows are made publicly by both parties before a holy and unchanging God, and they serve to construct a protective barrier around the marriage covenant for the good of the relationship.

Many couples don’t even include such vows in their wedding ceremonies today, dismissing them as outdated and overly harsh. The teachings of Christ on marriage were so vivid and severe to his audience that even the religious elites balked at them. The gospel of Matthew records Jesus speaking in no uncertain terms about the finality of the marriage covenant:

So they are no longer two but one flesh. What therefore God has joined together, let not man separate. – Matthew 19:6

However, even in Christian marriages the perceived definition of faithfulness occasionally drifts from that initial foundation and becomes blurred and tainted over time, with each partner internally defining faithfulness differently from the other. Add to this our capacity for sin, self-justification, and self-deceit, and you have a recipe for disaster.

Communication is Key

It helps to be upfront with one another in marriage, communicating openly and honestly about the expectations each of you have in mind regarding the boundaries that must not be crossed in order to honor your vows of faithfulness.

Even if you assume agreement with your spouse regarding your commitment to one another, this is something you can and should talk about together. As Scott Stanley, psychologist and University of Denver research professor on marriage and commitment writes,

“Most people expect conformity to a narrow definition of lifelong fidelity in marriage. While two people who are marrying can likely infer that this is implicitly agreed upon, they may still benefit from clarifying if both are on the same page about it. Absent marriage, it becomes all the more important for two people to get explicit.”

I have worked with couples in counseling who are facing a breakdown of marital faithfulness where one partner justifies a particular behavior by insisting that “it wasn’t actually cheating”, while the other insists that infidelity has occurred.

This only intensifies the heartbreak and pain of the wounded spouse (known in the field of psychology as “betrayal trauma”). The denial of guilt or wrongdoing by the unfaithful partner casts confusion and ambiguity on an already painful reality, which denies the betrayed partner even the dignity of truly grieving what has occurred.

From Negative to Positive Space

I hope you can begin to see how a lack of clarity about faithfulness in marriage leads to all sorts of problems. But I want to take a moment to shift our perspective on the subject.

Have you ever seen positive and negative space art? Usually, it is a black and white illustration in which the subject changes based on whether you focus on either the black or the white space in the image.

Although both pictures are present, the one you focus on becomes sharp and pronounced while the other fades into the background. With practice, you can even learn to switch your perspective back and forth between the two images.

Up until now in this article, we have taken a long look at the negative space of this topic (unfaithfulness or infidelity). This is the angle that the subject is most often approached from in our culture. But rather than focusing on what qualifies as infidelity, what if we approached fidelity (faithfulness) as something to be pursued, celebrated, and enjoyed?

I fear that media portrayals of affairs have made infidelity look appealing and exciting, as though it is something normal to desire. The obvious implication of this message is that faithfulness is just the opposite: dull and distasteful. Referring to one’s spouse as “the old ball and chain” is an example of this type of thinking.

There are examples of a positive perspective on faithfulness in the culture as well, we just have to look for them. The famous slogan of the Marines is “Semper Fi,” which is a shortened version of the Latin phrase Semper Fidelis, meaning “always faithful.”

High fidelity (or hi-fi) audio recordings are high quality, accurate reproductions of original sounds. As image-bearers of the Almighty, we might approach faithfulness as a way to accurately reflect God’s image on earth.

Even scriptural admonitions about marital faithfulness are expressed in the positive. One of my favorite passages on the topic is found in the book of Proverbs:

Drink water from your own cistern, flowing water from your own well. – Proverbs 5:15

Rather than focusing on what other “wells” you might miss out on by obeying this counsel, why not pursue the best possible way to “drink” from the well of your marriage partner?

The faithful marriage can and should be the most blessed marriage. Certainly, marriage is challenging and requires grit and hard work, but God is telling us in his word that marriage is a fountain to drink deeply from and enjoy, not a prison cell to escape.

That’s why the writer of Proverbs continues, “Let your fountain be blessed, and rejoice in the wife of your youth” (Proverbs 5:18). One of the most wondrous and profound ways to do so is through sexual intimacy with your spouse.

Sex is Only Safe in a Faithful Marriage

You may have noticed that cultural warnings to “practice safe sex” have been revised to “practice safer sex” to reflect the inability of measures like contraception or condoms to protect people from the many hazards of sexual activity outside of marriage. Long ago, the writer of Proverbs asked rhetorically, “Can a man carry fire next to his chest and his clothes not be burned?” (Proverbs 6:27).

Christian and secular sources alike recognize the inherent risks in sexual activity, which are impossible to avoid completely. The Johns Hopkins School of Medicine website features an article entitled, “Safer Sex Guidelines: What is Safe Sex?” The article warns readers:

“Having sex with only one partner who only has sex with you when neither of you has a sexually transmitted infection (STI) is believed to be safe. However, many healthcare professionals believe there really is no such thing as safe sex. They believe the only way to be truly safe is not to have sex because all forms of sexual contact carry some risk.”

Even when there is no apparent physical risk, as in the case of sex within a faithful marriage involving two partners who have not engaged in prior sexual activity, there are still emotional risks to the intense vulnerability of sex. This is why even in marriage, sex must flow out of a complete emotional, physical, and spiritual commitment to one another. As Timothy and Kathy Keller note in their book The Meaning of Marriage,

“Indeed, sex is perhaps the most powerful God-created way to help you give your entire self to another human being. Sex is God’s appointed way for two people to reciprocally say to one another, ‘I belong completely, permanently, and exclusively to you.’ You must not use sex to say anything less…So according to the Bible, a covenant is necessary for sex. It creates a place of security for vulnerability and intimacy. But though a marriage covenant is necessary for sex, sex is also necessary for the maintenance of the covenant. It is your covenant renewal service.”

The Kellers remind us of the incredible blessing that sex can be to a faithful marriage. It solidifies, signifies, and celebrates the beautiful and wholehearted commitment that marriage is meant to be. In fact, marriage was designed by God as a symbol of the union we are meant to have with Him. As the Kellers write, “The best marriages are pointers to the deep, infinitely fulfilling, and final union we will have with Christ in love.”

If you and your spouse have suffered the devastating effects of infidelity, or if you simply want to help your faithfulness flourish in your marriage for years to come, please don’t hesitate to reach out to me or another Christian counselor today.