Theology of the Body - Chapter 3 - Sexual Authenticity



Read 1 Thessalonians 4:3–5


The world treats bodies like objects, encouraging cheap sex without meaning. The Church teaches chastity, and the reason behind this teaching is sexual authenticity.

Context: Lust

We live in a throw-away society. Fast food and plastic plates — our culture is full of the cheap and easy. Unfortunately, this mentality bleeds into our sexuality. America is obsessed with sexual counterfeits. From the college hook-up culture to pornography to strip clubs and more, we see fake sex everywhere. All of us must ask ourselves: Do we really want counterfeit sex, or do we want something real? At the heart of the Church’s teaching on chastity is an encouragement to turn away from fake sex and choose the real thing.

In this Bible study, we’re going to talk about one of the things which lies at the heart of counterfeit sex: lust. In Matthew 5:27 – 28, Jesus gives us some challenging words: “You have heard it said, ‘You shall not commit adultery.’ But I say to you that everyone who looks at a woman lustfully has already committed adultery with her in his heart.” What strong words! John Paul II reads this passage to say, “Everyone who looks at a woman [reductively] has already committed adultery with her in his heart.” What does John Paul II mean here? Well, we know from before that bodies in themselves aren’t bad; they’re in fact very, very good. In fact, bodies are an essential part of the human person. Human bodies and souls exist as a single entity: They cannot be separated! One of the most beautiful things about humans is that we are a body-soul composite and we thereby bring together the spiritual and material worlds! For this reason, bodies are deeply good things.

That said, unfortunately bodies are so good, that sometimes we focus exclusively on the body, forgetting about the whole person, and this is what happens in lust. When a man or woman lusts, they’re not looking at a whole person; rather, their gaze stops at the surface. Just like John Paul II said, lust reduces the person to the body, ignoring the whole picture. In this way, lust stops at the cheap, easy surface of sexuality, missing the real thing.

Some argue that lust should not be considered a sin. After all, it doesn’t seem like lust hurts anyone, so what’s the problem? The problem with lust is that lustful actions don’t treat people like people; lustful actions treat people like objects, and this does A LOT of harm. Lust takes a whole person, a body-soul union, and cuts that person into two pieces: a body and a soul. When we look at someone lustfully, we do violence to them with our eyes. And lust does not only harm the person who is lusted after; it also harms the person who is lusting. Think about it: Our minds desire consistency, and if we mentally separate other people from their bodies, we’ll do the same to our own identity. If we view other bodies as objects for consumption, we will inevitably view our own bodies as mere objects of pleasure (TOB 59:3).

Deep down, we know this isn’t true. We’re not meant to be cut to pieces. The human body and soul are in union, and the one cannot exist without the other. Lust denies this truth. It turns people into cheap, counterfeit versions of our authentic, embodied, sexual selves. In this way, when Christ challenges us to overcome our lust, He is challenging us to learn to see others in accord with the truth of their person. Thus, the question for all of us is whether we’re willing to respond to Christ’s challenge and learn how to see!

Main Thing: The Language of the Body

Lust and counterfeit sex are as old as the Garden of Eden. Recall from our previous studies: Genesis 3:6 – 7 shows that after Adam and Eve ate of the fruit of the Tree, “The eyes of both were opened, and they knew that they were naked; and they sewed fig leaves together and made themselves aprons.” John Paul II reads these verses to mean that Adam and Eve lost their ability to see the body in the way it was meant to be seen. After sin, when Adam and Eve saw each other, they no longer saw everything that we discussed in the first two chapters (Trinitarian Love, Christ and the Church, etc.). Adam and Eve lost the ability to see correctly. John Paul II says that Adam and Eve lost their ability to communicate truthfully according to the “Language of the Body.”

The Language of the Body is foundational for every one of us. It’s the way we live, move and have our being. John Paul II says, “Man is constituted is such a way…that the deepest words of the spirit — words of love, gift, and faithfulness — call for an appropriate ‘language of the body.’ And without this language, they cannot be fully expressed” (TOB 104:7). The language of the body is not just any language; it is a language we desperately need! Through our bodies, we express the deepest things in our hearts. This is why sex, if experienced correctly, is such a wonderful gift! It allows us to say things we would not otherwise be able to say! As John Paul II himself says, it is “precisely on the level of this ‘language of the body…[that] man and woman reciprocally express themselves in the fullest and most profound way!” (TOB 123). The key to happiness here is learning to speak this language, according to our unique vocation, in authenticity!

Think of the language of the body as a letter sent from God to humanity. The letter is beautiful, and God wants to use the letter to communicate His love. Now imagine if a thief were to steal this letter, delete some of the most important parts and add a few twists of his own. This would ruin the letter! And this is exactly what Satan wants to do. Satan knows our bodies are important. We can use our bodies to say true things or false things, but either way, our bodies will speak loudly. Thus, it is crucial that we learn to speak the truth with our bodies. We must learn the value of sexual authenticity!

Application: Speaking Truth with Our Bodies (Two Analogies)

Sex is like a sacred letter written from God to humanity, and we want to read it correctly. The virtue that protects this sacred letter is chastity. Speaking of chastity, St. Paul says, “For this is the will of God, your sanctification: that you abstain from unchastity; that each one of you knows how to keep his own body with holiness and reverence, not as the object of lustful passions” (1 Thess 4:3 – 5). St. Paul knows that sex is sacred! He knows that the body speaks a precious language! But he is also familiar with human nature, and he knows it is easy to use the body in a deceptive way instead of an authentic way. Thus, he encourages us to keep or protect the body in “holiness and reverence.” In so doing, a chaste person can preserve their ability to speak the language of the body rightly. Just like preserving a letter, chastity helps us preserve the language of the body! Chastity heals our eyes and allows us to read this sacred language. In this way, chastity is nothing more than the virtue which enables us to see and be seen.

We have already said that lust is the sin which keeps us from viewing the body correctly. So, you might wonder, how do we escape lust? What is the alternative? Just like St. Paul said, the answer is chastity, which means living in accord with the truth of our bodies. You might call it sexual authenticity. The truly chaste person is not only someone who does the right thing, but also someone who desires to do the right thing. Drawing from the letter analogy, the problem is not always that the letter is distorted — the problem is that we don’t have the eyes to read the letter! For the truly chaste person, doing the right thing is not a struggle because they have trained their desires to desire correctly. This kind of chastity answers Jesus’ call to purify our hearts.

Let’s think about chastity in terms of two analogies. First, consider an Olympic athlete, say a soccer player named Michael. Michael is a good soccer player, but he wasn’t always so good. Michael practiced a lot. If Michael had not practiced, he wouldn’t have been able to make the split-second decisions necessary to win games. It was practice that gave Michael the freedom to play soccer well. But not everyone is so free. Poor soccer players are plagued by indecision. Such a person might wonder, “Should I pass right…or maybe pass left…take a shot…or maybe keep dribbling?” But Michael is not plagued by such indecision; he simply acts. He does not hesitate because he has trained himself to desire the correct things. Unlike the unskilled soccer player who sees a million different options, Michael sees only one option — the best option — and he takes it.

Olympians are skilled athletes, and becoming a skilled athlete requires virtue. A virtue is a habit which enables a person to desire and act in accord with their true self, living in accord with the fullness of their being. Now chastity is the virtue in the Church which concerns sexuality. Olympians train their bodies, and this training enables them to compete well. We’re called to do something similar with sexuality.

Just like an athlete, if we are willing to suffer, denying ourselves certain pleasures, we can train our bodies to desire the right things. This is true sexual freedom: the ability to desire as we ought to desire and live in accord with that desire. Training made Michael more, not less, of a soccer player, and the same is true for chastity. When we become more chaste, we become more sexually alive! Unfortunately, contemporary culture tells us just the opposite.

But, you might say, don’t I have the right to be creative, to express myself as I see fit? To be sexually promiscuous is to be free! Well, consider this. Do lust and sexual promiscuity actually make us free? This brings us to our second analogy. Instead of an Olympian, let’s consider a musician, say Beethoven. Beethoven’s music is brilliant. But, you might ask, how did Beethoven become such a good musician? For one, Beethoven spent years learning to play the piano. Furthermore, he learned the rules of music. He learned that certain notes go well together, that certain rhythms are intuitively appealing and that certain harmonies fit well with certain melodies. He learned that music has a certain order. Beethoven received the musical tradition, the rules and the wisdom of history’s greatest musicians. He then incorporated this tradition into his muscle memory. And here’s the important part. Learning these rules did not hinder Beethoven’s creativity — it did just the opposite: It brought Beethoven’s music to life!

What was true for Beethoven is also true for sexuality. One might say that music is like a beautiful language that enables man to say things he otherwise would not be able to say, and the same is true for our bodies. We’re meant to learn from the language of the body, and we’re meant to speak it ourselves! The virtue of chastity is the virtue that enables us to speak the language of the body in authenticity. We said earlier that the pure person holds his body in reverence, keeping it undefiled from the things of this world. To preserve our sexuality is like a musician preserving their ears. The best musicians often wear ear plugs in loud settings so as to preserve their hearing. They want to keep their ears sensitive to the smallest, most subtle sounds. Any medical doctor will tell you that the ear is a delicate organ, but sexuality may be even more delicate.

This is why the notion of sexual experimentation is a lie! Our culture tells us that careless, unrestricted sex will make us happy. But this is false. Just like loud music at a rock concert, counterfeit sex inhibits our ability to listen and speak with our bodies. Remember, the virtue of chastity is perhaps nothing more than the ability to see and be seen, but learning to see involves preserving our eyes. Ruined eardrums are no good for a musician, and sexual brokenness is no good for a person. The Church wants us to train our minds and our eyes to read the language of the body in sexual authenticity. Once again, we see the Church’s teachings do not restrain our sexuality. On the contrary, the Church helps us live our sexuality authentically.

When it comes to chastity, it is important that we get practical. Athletes and musicians need to practice, and the same is true for chastity. Repetition breeds virtue. As fallen human beings, we have a natural tendency to lust, and we need teammates and coaches to help us become more virtuous. Don’t pursue this virtue alone! Make use of the sacraments, spiritual mentors and your brothers and sisters in Christ. We all need support and accountability. Take some time today to think about practical steps forward in chastity.



1 Thessalonians 4:3-5


Note: This study addresses some similar themes as addressed in the first chapter. Whereas the first chapter discussed the spousal analogy and shame, this chapter focuses on sexual authenticity, the language of the body and lust. Having met with your students several times, this might be a good opportunity to get a little more practical. During the application section of this study, do not be afraid to discuss specific issues your students have with chastity and how to grow with respect to these difficulties. You might ask, for example, what practical steps your students might take to become more chaste in their romantic relationships or any other specific struggles they might have.


1. Introduction: The Challenge of Chastity

A. Read: Matthew 5:27 – 28.

B. Place yourself in conversation with Jesus. Imagine if He told you that “everyone who looks at a woman lustfully has already committed adultery with her in his heart.” What are you thinking?

Answer: Allow the group to discuss.

C. What do you think Jesus is saying?

Answer: Allow the group to discuss. Allow students to sit and ponder this for a while. Christ speaks with a lot of gravity, and it’s important that we allow things to sink in.

D. Say: In this passage Jesus tells us the heart of chastity is not what we do with our outsides but rather what we do with our insides. At the core, what do you think is the problem with lust?

Answer: Allow the group to discuss. Note, these questions are designed to set students up to see that lust is a counterfeit. It reduces the person to an object for pleasure.


2. Lust

A. Read Genesis 3:6 – 7. What do you remember about this passage from our last study?

Response: Allow group to discuss.

B. Remember from our first Bible study that something changes at this point in the story. Genesis says, “Then the eyes of both were opened, and they knew they were naked; and they sewed fig leaves together and made themselves aprons.” Now of course Adam and Eve knew they were naked before they ate from the tree, so something changed in their experience of nakedness. Like we said in the first study, Adam and Eve now experience shame. But shame isn’t the only thing that entered the picture. Adam and Eve also experience another thing: lust.

C. Ask: What would cause Adam and Eve to cover themselves? Adam and Eve knew (in some sense) that they were naked before Eve ate the apple, so what changed? What does this have to say about lust?

Answer: Allow the group to discuss.

D. John Paul II interprets these verses as humanity’s first experience of lust. He says that Adam and Eve learned to view each other reductively. What does this mean?

Answer: Lust reduces the whole person to just a part of the person. In this way, lust is a lie. Our materialistic culture wants things cheap and easy. We like fast food, paper plates and cheap entertainment. Unfortunately, this mentality bleeds into our sex lives. We see this in things like the hook-up culture, porn and strip clubs. Sexual counterfeits are everywhere, but they only imitate the real, and they cannot give us what we truly desire.

E. Do you see a connection between lust and shame?

Response: When we act lustfully towards someone, we often feel ashamed. Further, when we feel someone looking lustfully at us, we also feel ashamed. Thus, lust and shame are two sides of the same coin. If we want to overcome shame, we must learn to overcome lust

F. Say: Lust does not only affect how we view others; it also affects how we view ourselves. You see, if we reduce other people to objects of pleasure, dwelling on only superficial qualities, we will inevitably think of ourselves in the same way. Our minds desire consistency, and if we limit ourselves to valuing superficial qualities in other people, we will inevitably value those same qualities in ourselves (Note: This might be a good time to share a personal story of your own experience with lust). Have you ever experienced this? Have you ever felt that, by reducing other people, you have reduced yourself?

Answer: Allow the group to discuss. Maybe look for specific examples as to how group members might have experienced this.

3. The Language of the Body

A. Ask: John Paul II says the deepest things in the human heart require the “language of the body. Without this language, they cannot be fully expressed” (TOB 104:7). For John Paul II, the body is a sacred language which allows us to say the deepest things on our hearts. Have you ever thought about the body in this way?

Response: Allow the group to discuss.

B. Think about physical expressions like handshakes, hugs, kisses, etc. All these physical expressions say something. Let’s think about today: How have you spoken with your body language today?

Response: Allow group to discuss.

C. Ask: Have you ever lied with these less significant physical gestures? If so, what does it feel like when you do?

Response: Allow the group to discuss. The point here is to get your students to understand the language of the body in their own personal experience. Help them see that we naturally understand that the body does speak a language.

D. “The body tells the truth through faithfulness and love, and, when it commits ‘adultery’ it tells a lie…” (TOB 104:8). As you can lie in verbal language, it is possible to lie with the language of the body. Have you ever felt as though you’ve lied with your body? Note: This would be a great time to share some personal testimony.

Response: Allow the group to discuss.


4. Chastity and Authenticity

A. Read 1 Thessalonians 4:3 – 5. St. Paul says, “For this is the will of God, your sanctification: that you abstain from unchastity; that each one of you knows how to keep his own body with holiness and reverence, not as the object of lustful passions.”

B. What does this passage have to do with chastity?

Say: The body is sacred, and St. Paul knows it is sacred. Without the body, we cannot say the most important things in our hearts. The body is like a sacred letter, written from God to humanity. We don’t want to lose this letter. We do not want it to be destroyed. It needs to be protected! Chastity is the virtue that helps us read the language of the body in authenticity.

C. What are some practical ways in which we can “keep the body in holiness and reverence”?

Answer: This is a great opportunity to discuss modesty.

D. Ask: Do you feel as though you’re able to view another person’s body as an expression of their soul? Are you able to see members of the opposite sex as they’re meant to be seen?

Answer: Allow the group to discuss.

5. Application: The Virtue of Chastity

A. We all know it is difficult to speak the language of the body in truth. Our culture is so used to imitations and counterfeits that it is difficult to be authentic. It’s difficult to tell the truth. It’s like eating healthy: Fast food is everywhere. It’s quick, easy and readily available. Eating healthy requires a little more discipline. The following two analogies are helpful in understanding chastity. (Explain the Olympian and Beethoven analogies from the Leader Guide.)

B. Question: Just like with the Olympian, sexual discipline enables us to be more authentically sexual. It enables us to remain faithful to our spouses (whether current or future), preserving our sexuality for them in “holiness and reverence.” How do you think you might be able to grow in chastity?

C1  – Men: Men, we often struggle with control over our eyes, and we are prone to manipulate feminine emotions. How can we grow so as not to reduce a woman to her physical appearance? Also, what can we do to respect the feminine heart, not toying with female emotions?

Response: Allow the group to discuss. Give gender-specific directives tailored to the spiritual maturity of your group. Men must learn to have custody of their eyes, treating the feminine body as a gift from God to be held in reverence. Men often don’t realize that things like unrestrained flirtation can actually play with a women’s heart. Flirting is not necessarily a bad thing, but it is important that men learn to respect a woman’s emotional sensitivity.

C2  – Women: Women, it’s a cliché, but it’s often true that “men use love to get sex and women use sex to get love.” As women, it’s important that we learn to cultivate emotional chastity. Furthermore, we must learn the art of modest dress, both to respect our own dignity and to help men see our bodies correctly. What practical steps can we take to become more chaste?

Response: Allow the group to discuss. Give gender-specific directives tailored to the spiritual maturity of your group. Women must learn to have custody of their emotions and develop the virtue of emotional chastity. That is not to say that women do not struggle with chastity at a physical level, but a woman’s struggle is often different than a man’s struggle. In general, women need to pay more attention to custody of emotions. Finally, modest dress, dress that helps men experience the true beauty of the feminine person, can actually help men and women become more chaste.

C. How can we help each other to grow in control over our eyes and ears so that we might authentically speak the language of the body?

Response: Allow the group to discuss.

Leader Note: Here people might object that the sexual norms of the Catholic Church seem overly repressive. They hamper creativity. If this happens, you might choose to use the Beethoven analogy (or whatever musician you prefer). Learning the rules of music does not make someone less musically creative; it does the opposite. Also, feel free to take some freedom here with the application section. If the analogies are helpful, use them. If not, don’t use them. And finally, the final set of questions have been split into men (chastity of the eyes) and women (emotional chastity), but obviously both sexes struggle with both types of chastity, so you may choose to speak on both.

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