“You have heard that it was said, ‘You shall not commit adultery.’ But I tell you that anyone who looks at a woman lustfully has already committed adultery with her in his heart. If your right eye causes you to stumble, gouge it out and throw it away. It is better for you to lose one part of your body than for your whole body to be thrown into hell. And if your right hand causes you to stumble, cut it off and throw it away. It is better for you to lose one part of your body than for your whole body to go into hell.” (Matt 5:27-30)
1. What kind of world do we live in?
Living in a sex-saturated world: an endless onslaught
I was recently in Melbourne with my 18-year-old son to see the F1. During this time, there was a comedy festival taking place in another part of the city. My son urged us to buy tickets for one particular comedian—someone who was apparently very popular on TikTok. I tried to resist, saying that my overwhelming impression of modern stand-ups is that they saturate their material with themes of masturbation and sex, while filling every mid-sentence pause with the “F” and “C” words. I didn’t want to pay for this experience. My son assured me that the guy was funny. I relented and we booked tickets.
Waiting outside the venue, I was heartened at the sight of the clientele: they were mostly people in their 20s and 30s, and there was about a 4:1 ratio of females to males. Surely this demonstrated an expectation for courteous, tame and intelligent humour, not junior high school gutter stuff!
So what happened? The hour-long show was a rolling reel of masturbation jokes, blended with sex jokes about disabled people, and personal anecdotes about oral sex and more masturbation. And yes: all pauses and gaps were filled by the “F” and “C” words. My prophecy was correct.
What I didn’t predict—and what made me far more uncomfortable—was the audience’s response: they were rapturous—even euphoric. Every last one of them ended up on their feet. This actually shook me, because I had it in my middle-aged, daggy dad brain that people don’t want unsolicited sexual humour from a skinny, white male comedian. But that was the point: it wasn’t unsolicited. Just as long as there is consent in advance (which apparently only I had failed to give), normal people aren’t against grubby sexual humour. I left feeling I had participated in sex cult ritual.
But when I take a step back, I see that this is just a snapshot of our modern society: we live in a sex-saturated world.
Sexualised identities, individualism and happiness make criticisms immoral
If you’re familiar with Dr Carl Trueman’s book The Rise and Triumph of the Modern Self, you will understand how complicated even discussing sexuality has become. Personal identities have evolved from being psychologised to being romanticised, plasticised and now sexualised—such that the prevailing ideology now sweeping through our institutions, media and bureaucracies is that identity is defined by sexuality. Happiness is the prevailing lens that determines right and wrong in society. We are all highly individualistic. Sex is a de-personalised function.
What complicates things is that since identities are self-determined, sexualised and undergirded by the drive for happiness, traditional Christian teachings on sexuality feel wrong. To oppose a person’s sexual actions, beliefs or feelings risks causing them harm, which is immoral. So is anyone going to take Jesus’ words in Matthew 5:28 about lust seriously?
Technological exposure: another front facing young people
As a researcher of child and adolescent behaviours, I see another perspective worth adding to Trueman’s analysis: most post-internet people (that is, any person who lived their adolescent years with access to the internet) have had additional exposure to sexualised culture. Typically, a child gains access to the internet at around 11 years old. They get their first social media account at 11 years old. They encounter pornography at 11 years old. By age 15, 100 per cent of females and 90 per cent of males are active on social media, spending around two hours a day online. 70 per cent of males and 21 per cent of females regularly view pornography. Unsurprisingly, the more porn they consume, the more they will objectify women, seek out sexualised behaviour, have lower empathy and exhibit poorer conduct. They are also more narcissistic. So while the world’s values assault from outside, individuals are being shaped from within by technology.
Is anyone left listening?
Anecdotally, as a parent, educator and former youth worker, I see the effect culture is having on young Christians. There is an increased tolerance for sexualised behaviour—of casual sex, of sexual behaviours when dating, and of dating couples travelling alone together. Pornography addiction is rampant. Sexualised fashion and swimwear is normal. There’s a high tolerance for—and indifference to—consuming sexualised movies and shows. There’s also unfettered and endless self-promotion on social media, with Christian leaders often being the worst offenders for narcissistic self-promotion.
Furthermore, I detect a deeper resentment—even offence—at the traditional biblical teaching of sexual ethics and abstinence until marriage. Recently I was challenged by some young Christian men for speaking against their porn use, because “It’s private and none of your business”. I saw a lack of hunger for God’s will on these matters. Of course, not everyone is like this, but I feel the world is winning over many young Christian hearts and minds, and they don’t realise.
This is why people have to stop and listen to what Jesus says in Matthew 5:28, because he takes a blowtorch to our world’s hyper-sexualised values.
2. Does Jesus even care about my thoughts?
Blurred lines between actions and intent
It can be tempting to think that Jesus doesn’t care about what goes on in our heads. But when Jesus said lustful thoughts are akin to adultery, he made it clear that intent is on the same level as action. The Jews listening knew that adultery carried a death sentence (Lev 20:10). Lust, however, fell under the domain of the tenth commandment: “Do not covet” (Exod 20:17). But in declaring that unrestrained lust would warrant hell in Matthew 5:29-30, Jesus elevated the seriousness of sexual intent. God, who sees and knows all thoughts, will hold thoughts to account, just as the Law did with adultery—not with stones, but with hell.
The heart levels the playing field between the “righteous” and the “pagans”
This was confronting. The Jews of Jesus’ day prided themselves on their actions, which distinguished them from the Gentiles. But they were no different to the sex-saturated pagans around them: their hearts were full of the same motives. The heart, Jesus said in Matthew 15:19, is the root of sinful behaviour: “For out of the heart come evil thoughts—murder, adultery, sexual immorality, theft, false testimony, slander.” By promoting lust with adultery, and intent with action, Jesus levels the playing field between the religious and the godless, and reminds us that God will judge both.
Lust and sexual behaviours matter
However, this judgement is not just for the last day; God also judges now. There are contemporary consequences for misplaced sexual desire. For example, when God hands people over to their shameful lusts and sinful desires in Romans 1:24, 26, one of those consequences is increased engagement in sexually immoral behaviour: “God gave them over in the sinful desires of their hearts to sexual impurity for the degrading of their bodies with one another” (Rom 1:24). God gives people what they want, which becomes part of the punishment for their sin. Although our world celebrates sexual freedom and diversity, Romans 1:27 hints that there are negative consequences personally experienced from sexually immoral culture, with men receiving “in themselves the due penalty for their error”.
As a researcher on the negative effects of pornography and online sexualised media, I consistently observe these negative consequences. I see it individually, with people experiencing altered neurology, thinking and behaviour, and behaving at chronic and addictive levels. I see it relationally, with people exhibiting a self-focussed, unintimate and poorly informed sexuality that reaps dysfunctions, harms and insecurities in many relationships. I see it societally, with the private market of lust driving a pornified culture across mainstream media. We have a callous social soul that ignores the endless victims of pornography, increases the objectification of women, and creates mass sexual confusion among young people. To me, these are compelling arguments that our sexualised culture is punishing us.
Being clear about good versus bad sexual desires
When we discuss sexual thoughts and behaviours, we mustn’t lose sight of what the Bible says about sexuality. God is not against sex: he designed it—it is his gift—but it has parameters. Matthew 19:5-6 makes it clear sex is for the exclusive domain of marriage:
“‘For this reason a man will leave his father and mother and be united to his wife, and the two will become one flesh’? So they are no longer two, but one flesh. Therefore what God has joined together, let no one separate.”
Sex physically bonds male and female, consolidating their profound oneness (relational, emotional and spiritual), which God himself orchestrates. Similarly, Hebrews 13:4 says, “Marriage should be honoured by all, and the marriage bed kept pure, for God will judge the adulterer and all the sexually immoral”. Marriage is sacred. Sexual desires for one’s spouse is a good use of God’s gift. To mess with marriage is to mess with God. Sexuality outside of the marriage parameter is what the Bible calls sexual immorality.1
Given everything I have said so far about lust, sexual desire, judgement, and the sacredness of sex, it should be abundantly clear that Jesus very much cares about our thoughts.
3. Is sexual immorality really a problem?
When sex rivals God
But why is sexual immorality and sexual desires such a problem? Why is God offended by them? There are a number of reasons. Notwithstanding the fact that self-centred, unloving behaviour that brings harm to another is always wrong, it’s much more personal to God, because misplaced sexuality is idolatrous. It rivals God. In Romans 1:24-26, we see that when people exchange the truth of God for lies, they surrender to sexual feelings, lusts and debauched behaviours. God gets replaced by sex.
History is littered with examples of false religions fusing sexual behaviours with their worship. This would explain why the apostles singled out sexual immorality as an absolute “no go” area for the Gentile Christians in Acts 15:20, 29: these behaviours were too closely aligned with pagan idolatry. Furthermore, have you noticed that although our western world is essentially atheist/agnostic now, it still defends modern sexual ethics just like religious zealots?
Immoral sexual behaviour always rises to rival God. It is idolatrous. How many of us right now are aware, in our hearts, that our knees are bent not to Jesus, but to the idol of sexual fantasy and self-gratification?
When sex corrupts God’s body
Sexual immorality also corrupts the body of Christ. In 1 Corinthians 6, we read about how our union into the body of Christ, through faith in Christ and the receiving of the Holy Spirit, makes us incompatible with sexual immorality: “The body, however, is not meant for sexual immorality but for the Lord, and the Lord for the body” (v. 13). Our private thoughts and actions cannot be divorced from Jesus himself, since we are united to him. Thus unchallenged sexual sin is both deeply insulting to him and worse, violating of him, and it risks the very nature of our salvation, which is trusting in Christ as our perfect substitute.
When sex mocks the gospel
Lastly, sexual immorality is an affront to the gospel itself. We learn in Ephesians 5 that marriage, at its deepest meaning, is a metaphor for Christ and the church. That is, the eternal union achieved between Christ and his people through his death and resurrection is pre-empted by the marriage union. To embrace sexual immorality is to dishonour marriage, and to dishonour marriage is to dishonour that to which it points—the salvific work of Christ. Casual sex, pornography, adultery—these are mockeries of Christ and his church.
So it is no wonder Jesus emphatically condemns sexual lust. It is a doorway to idolatry, a corruption of the body of Christ and a mockery of the gospel. When Jesus said, “For where your treasure is, there your heart will be also” (Matt 6:21), he then said, “The eye is the lamp of the body” (Matt 6:22). We have to guard our eyes and thoughts, or else our hearts will follow after what we fixate upon, and desire will take hold.
4. What do we do about sexual lust and behaviour?
Cutting it off and fleeing
So what do we do about these powerful, innate forces within us that the world says to embrace? Of lust, Jesus says to take whatever action necessary to avoid it—to “cut it off” (Matt 5:30). Similarly, Paul says to “flee sexual immorality” (1 Cor 6:18). These are strong words we would do well to heed!
Committing to school
I love what Paul says in Titus 3:14: “Our people must learn to devote themselves to doing what is good”. The word for “learn” is actually “be schooled”: it means to take action and submit oneself to a learning process. This is very useful for us, because the Christians in Crete, where Titus was leader, were pagan, worldly, pleasure-seeking addicts. They experienced huge cultural pressures to be selfish and lazy that are very similar to our times. But they needed to step up, take action, and go to school to learn change.
People struggling with sinful temptations like porn addiction need to understand that they have to step up and take action. You have to learn to change. It’s not a passive process; it’s active. If you say, “But I prayed and prayed, and God didn’t take it away”, but didn’t make any effort to change, learn about yourself and commit to concrete processes, you are not listening to God’s instruction.
Letting the gospel teach godliness
Who were the Cretans to learn from? Their teacher is the gospel. The person, work and teaching of Jesus is the agent for change:
For the grace of God has appeared that offers salvation to all people. It teaches us to say “No” to ungodliness and worldly passions, and to live self-controlled, upright and godly lives in this present age … (Titus 2:11-12)
The significance of this should not be lost on us: in the struggle to resist sexual temptation and behaviour, we can become mired in despair, indifference, guilt and repeated mistakes. But the gospel tells us we are loved, that God wants to forgive us, that he knows us in our weaknesses, and that he’s paid the price for our sin. The gospel shows us what sacrificial love is—how like Christ, we can put others first, and how humans have been both created in his image and redeemed as children of God. The gospel teaches how to take off the old self and put on the new (Col 3:9-10), and how to learn and imitate the character of Christ (1 Cor 11:1; 1 Pet 2:21). The gospel teaches us what’s important in the world order—not personal happiness, but the salvation of the lost, the building up of the church, and bringing glory to God.
Being heavenly minded
In addition, the gospel points us forward to heaven, where God is holy and where we too will be holy. Colossians 3:1 says, “[S]et your hearts on things above, where Christ is, seated at the right hand of God”, and in verse 4, it also says, “When Christ, who is your life, appears, then you also will appear with him in glory”. One day we will be in heaven with Christ. One day we will be like Christ. This is our future.
This future gives us fuel to live out the words of 1 Peter 1:16 (“Be holy, because I am holy”) and also Jesus in Matthew 5:48 (“Be perfect, therefore, as your heavenly Father is perfect”). Heaven drives our hearts to embrace now what we will be for eternity.
5. How do we respond in these modern times?
So how should we respond to Jesus’ words and warnings in Matthew 5, which are supported by the rest of the Bible? I would suggest three things: repent, change and act.
If you are a person feeling trapped by sexual lust, you may also be burdened by guilt and shame. It’s actually good that you remember that lust is sinful, offensive to God and harmful to others. What Jesus desperately wants is to forgive you, because he loves you. Remember: no sin is too great and no repeated failure too unforgivable. Jesus knows our weaknesses, and has already loved us at our most unlovable. But he wants us to return to him and allow him to lead us from sin to righteousness. Remember the woman caught in adultery in John 8: Jesus didn’t judge and he didn’t ignore her sin. He said, “Neither do I condemn you … Go now and leave your life of sin.” If you don’t fear the sin, you won’t seek change.
If you keep repeating the same behaviours, ask yourself: are you taking seriously the steps required to change? I find that once we analyse people’s behaviours, we see regular, predicable patterns. They may have triggers, environments, times and locations where temptation is more powerful. They may also have more complex and deep feelings that coexist with these temptations—past hurts or traumas. But if you haven’t taken steps to dissect and untangle your thoughts and behaviours, don’t expect to go far.
I recommend seeing counsellors who are trained and experienced in these areas. They are also confidential, which reduces embarrassment. I also recommend that you talk openly with close contacts at church. You aren’t alone. Finally, I also recommend that you explore community recovery programs in your local area. There are various respectable courses out there. I run a five-week course called Resist. It’s easier to change together than on one’s own. But if you don’t make serious efforts to change, don’t expect much.
Lastly, I think we can go further than individual repentance and change: we can act. Christians should make a stand against society’s sexual culture. Here are a few thoughts on how we can do this.
Think globally and act locally. Saying you oppose sexualised culture while still watching sexualised shows, supporting sex-promoting artists, exhibiting sexualised behaviour in your own online presentation, and openly endorsing other people’s ungodly sexual influence seems rather hypocritical. We have an opportunity as God’s people to be countercultural. We can act. This is not just on the person struggling with lust; all of us can do this.
Parents have an enormous burden to educate their children while managing technology and the internet. The tools are out there, but how much effort will you put in? It means a lot of hard work, upskilling yourself to think through these things, and figuring out what it means to protect kids from the problems of technology and from the messages of the world.
Christian schools, which are right on the frontline of the cultural battles for our young, have special challenges and responsibilities here: not only can they help shape the minds of their kids and protect them, they can also make them use technology as part of their learning. Are schools being sensitive? Are they doing the right things to help their communities move forward? Do they teach kids how to combat sexual culture?
Finally, churches need to think through how to be countercultural to the sexual values of a world obsessed with lust and sexual consumption. They need to do this with rigour, regularity, sensitivity, care and seriousness. How does your church teach the Bible’s view of sexuality? How does your church address the challenges their youth are up against? How does your church equip parents to teach their children the gospel? If these things aren’t happening, what needs to change?
If we remain silent and indifferent, we leave the hearts of our young people exposed to the world’s unrelenting onslaught and to a God who calls all thoughts to account. Let’s be people of repentance, change, and action, and not permit lust to compromise our hearts, our communities, our relationships and our salvation.
Bible quotations are from THE HOLY BIBLE: NEW INTERNATIONAL VERSION®. NIV®. Copyright © 1973, 1978, 1984, 2011 by International Bible Society, www.ibs.org. All rights reserved worldwide.
1 Interestingly, the Greek word mainly used for sexual immorality is “πορνεία/porneia”, meaning “sexually immoral writings”, and the word “pornography” is derived from it.