The bombshell section on lust from Matthew 5:28 – But I tell you that anyone who looks at a woman lustfully has already committed adultery with her in his heart – makes for desperate reading for many Christians. We live in a sex-saturated world and not many of us are exempt from these hard words once thoughts and desires are introduced. 

Those familiar with Dr Carl Trueman’s The Rise and Triumph of the Modern Self will understand how complicated even discussing sexuality has become. Personal identities have evolved from being psychologised, romanticised and plasticised to now being sexualised. The prevailing ideology 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, and we are a highly individualistic society. Sex is a depersonalised 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 deemed immoral. 

Is anyone going to take Jesus’ words about lust seriously?

As a researcher of child and adolescent behaviours, I see another perspective worth adding to Trueman’s analysis. Most post-internet people (any person who lived their adolescent years with access to the internet) have had additional exposure to sexualised culture. Typically, a child now gets access to the internet at around 11 years of age. They get their first social media account at 11. They encounter pornography at 11. 

By the age of 15, 100 per cent of females and 90 per cent of males are active on social media, spending about two hours a day online. Seventy 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 poorer conduct. They are more narcissistic. So, while the world’s values assault from outside, individuals are being shaped from within by technology.

Seventy per cent of males and 21 per cent of females regularly view pornography.

Anecdotally, as a parent, educator and past youth worker, I see the effect this is having on young Christians. There is an increased tolerance for sexualised behaviour. Of casual sex, sexual behaviours when dating, dating couples regularly travelling alone together. Rampant pornography addiction. Sexualised fashion and swimwear. A high tolerance for, and indifference to, consuming sexualised movies and shows. Unfettered and endless self-promotion on social media. 

Their ministers, sadly, are often shining examples for narcissistic self-promotion. More, 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, none of your business”. There is 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 know it.

We have to stop and listen to what Jesus says in Matthew 5:28, because he takes a blowtorch to our world’s hypersexualised values. 

Why does Jesus care about my thoughts?

When Jesus says lustful thoughts are akin to adultery, he makes clear that intent is on the same level as action. Now, those Jews listening knew that adultery carried a death sentence (Leviticus 20, John 8). Lust, however, fell under the domain of the 10th Commandment (do not covet). But in declaring that unrestrained lust would warrant hell (Matt 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.

There are contemporary consequences for misplaced sexual desire

This was confronting. Jews 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 Matt 15:19, is the root of sinful behaviour. 

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 the increased engagement in sexually immoral physical behaviour. God gives people what they want, which is the punishment. For although our world celebrates sexual freedom and diversity, Rom 1:27 hints that there are negative consequences personally experienced from sexually immoral culture. 

As a researcher on the negative effects of pornography and online sexualised media, these negative consequences are consistently observed. I see this individually with altered neurology, thinking and behaviour – and at chronic and addictive levels. I see it relationally with self-focused, 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 from pornography, increases the objectification of women and creates mass sexual confusion among young people. These are compelling arguments that sexualised culture is punishing. 

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. Matt 19:5-6 makes it clear it’s for the exclusive domain of marriage. It physically bonds the male and female, consolidating their profound oneness (relational, emotional and spiritual), which God himself orchestrates. Heb 13:4 reaffirms the sacred nature of marriage, while warning that to mess with it is to mess with God. By the way, sexual desire for one’s spouse is a good use of God’s gift.

Sexuality outside of the marriage parameter is what the Bible calls sexual immorality. Interestingly, the Greek word mainly used is porneia from which “pornography” derives (meaning sexually immoral writings). 

Is sexual immorality really a problem?

Why is God offended by sexual immorality (including sexual desires)? For a number of reasons. Notwithstanding self-centred, unloving behaviour that brings harm to another is always wrong, it’s much more personal to God. Misplaced sexuality is idolatrous. It rivals God. Again, in Romans 1 we see people exchange the truth of God for lies and they surrender to sexual feelings, lusts and debauched behaviours. 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 for Gentile Christians in Acts 15 – these behaviours were too closely aligned with pagan idolatry. 

Have you noticed that, although our Western world is essentially atheist/agnostic now, people still defend modern sexual ethics 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 bow not to Jesus but to the idol of sexual fantasy and self-gratification? 

Sexual immorality also corrupts the body of Christ. In 1 Cor 6 we read how our union into the body of Christ, through faith in Christ and receiving of the Holy Spirit, makes us incompatible with sexual immorality: “The body... is not meant for sexual immorality but for the Lord, and the Lord for the body” (6:13). 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 – worse, violating of him – and risks the very nature of our salvation, which is trusting in Christ as our perfect substitute. 

Sexual immorality is also an affront to the gospel. 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. 

It is no wonder Jesus emphatically condemns sexual lust. It is the doorway to idolatry, corrupts the body of Christ and is a mockery of the gospel. When he 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”. We have to guard our eyes and thoughts, or our hearts will follow and desire will take hold. 

What do we do about sexual lust and behaviour?

So what do we do about these powerful, innate forces that the world tells us 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). Strong words, but how?

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 becomes very useful for us because the Christians in Crete who Titus led were pagan, worldly, pleasure-seeking addicts. They had huge cultural pressures to be selfish and lazy. Very similar to our times. But they needed to step up and go to school to learn change. And who were they to learn from? Titus 2:12 says their teacher is the gospel. The person, work and teaching of Jesus is the agent for change. 

This can’t be lost on us, because in the struggle to resist sexual temptation and behaviour we can get lost in despair, indifference, guilt and repeated mistakes. The gospel tells us that we are loved, God wants to forgive, that he knows us in our weaknesses and that he’s paid the price. The gospel shows us what sacrificial love is, how – like Christ – we can put others first, 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, how to learn and imitate the character of Christ. The gospel teaches what’s important in the world order – not personal happiness but the salvation of the lost and building up of the church, all bringing glory to God. And the gospel points us forward to heaven, where God is holy and where we, too, will be holy. 1 Peter 1:16 says “Be holy, because I am holy”, and Jesus says in Matt 5:48, “Be perfect, therefore, as your heavenly Father is perfect”. Heaven drives our hearts to embrace now what we will be for eternity. 

Where to from here?

For a good response to Jesus’ words and warnings in Matthew 5 (supported by the rest of the Bible!) I would suggest three things: repent, change and act.

If you are feeling trapped by sexual lust, you may be burdened by guilt and shame but it’s actually good that you remember this is sinful, offensive to God and harmful to others. What Jesus desperately wants is to forgive you, because he loves you. No sin is too great, no repeated failure too unforgivable. Jesus knows our weaknesses and has already loved us at our most unlovable. 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 her or ignore her sin but 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 to change. 

If you keep repeating the same behaviours, are you taking seriously the steps required to change? I find once we analyse people’s behaviours there are regular, predictable patterns. There are triggers, environments, times and locations where temptation is more powerful. There may also be more complex and deep feelings that coexist with these temptations – maybe 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 counsellors, who are trained and experienced in these areas. They are also confidential, which reduces embarrassment. I also recommend you talk openly with close contacts at church. You aren’t alone. And I recommend you and your community explore recovery programs. There are various respectable courses – I run a five-week course called “Resist”. It’s easier to change together than on one’s own. If you don’t make serious efforts to change, don’t expect much.

We can go further. I think Christians should make a stand against society’s sexual culture. Think globally and act locally. Saying you oppose sexualised culture but still watch sexualised shows, support sex-promoting artists, are sexualised in your own online presentation and openly endorse other people’s ungodly sexual influence seems rather hypocritical. 

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? Christian schools, right on the frontline of the cultural battles for our young, have special challenges and responsibilities here. Do they teach kids how to combat sexualised culture? 

Lastly, what does it mean to be a countercultural church in a sexualised world? I would hope each of you, in your church communities, think through this with rigour and care. If we remain silent and indifferent, we leave the hearts of our young people exposed to the world’s unrelenting onslaught, and a God who calls all thoughts to account. Let’s be people of action. 

This is an edited version of a talk given by the Rev Dr Marshall Ballantine-Jones at the Centre for Christian Living on May 4.