From my friend William P. Farley’s latest book, Gospel-Powered Parenting: How the Gospel Shapes and Transforms Parenting (P&R, 2009):
“Thomas Chalmers (1780-1847), a Scotch Presbyterian, wrote a famous essay entitled The Expulsive Power of a New Affection. In it Chalmers proposes that the best way to overcome the world is not with morality or self-discipline. Christians overcome the world by seeing the beauty and excellence of Christ. They overcome the world by seeing something more attractive than the world: Christ, ‘in whom are hidden all the treasures of wisdom and knowledge’ (Col. 2:3). A man who owns an Acura is not interested in a Geo Metro. In the same way, Christian parents try to make Christ and his kingdom glorious. Their children conquer the lusts of this world with a higher passion: the moral beauty of Christ.
By contrast, defensive parents have little confidence in the attractiveness of the gospel. They think the world is more powerful. Fundamentally, they are not confident in the gospel’s power to transform their children from the inside out. They do not believe Jesus’ words, ‘Take heart; I have overcome the world’ (John 16:33). They have little confidence in the world-conquering power of new birth.
My wife and I have seen the fruit of this approach in our own experience. My five children all attended public high schools, and then the eldest four matriculated to a state university. Despite the raunchy non-Christian—even anti-Christian—environment (and it was foul), they thrived spiritually. Why? Through the miracle of new birth, God changed their hearts. To them the Holy Spirit had begun to unveil the superlative value of Jesus Christ. The conviction that all their happiness was tied up in their relationship with Christ had begun to bud and grow. The world’s allurements could not compete.” [pp. 24—25]
Tony Reinke 
The problem with the Acura analogy is that an Acura owner does not by his very nature have a Geo-Metro in his heart.
A child whose heart has been changed from stone to flesh, by his very nature will begin to love Christ, but we have no guarantee that our children will all get saved (in fact, we have few examples in Scripture of men who had all of their children come to Christ), nor are we to take their profession of salvation as anything more than it is, a profession. To be sure, I point my children to the beauty of Christ but I also hold them to morality and self-discipline.
And here’s the great part, this is exactly what Scripture tells us to do. Paul did not cease to buffet his body after his Damascus road experience. But instead, this man, who clearly loved the beauty of Christ in ways that should humble every one of us, also held to the physical and spiritual discipline of the faith.
Wow! This must be a great book, both you and Tim Challies posted your reviews on this book the same day. Look forward to purchasing and even more implementing it’s wisdom.