My husband, a math teacher, was trying to explain a complicated theory to me. It involved (from what I could gather) pictorial representations of mathematical equations. As hard as I tried, I just couldn’t grasp what he was talking about. “I’m sorry, hunny,” I said, “but you’ve lost me.”

“You lost me” is the phrase we use when we don’t understand something someone is trying to tell us. It isn’t that we’re not listening or not trying, it’s that our brain can’t make sense of the information being presented. Such is the thesis of David Kinnaman’s You Lost Me: Why Young Christians Are Leaving Church… and Rethinking Faith (Baker Publishing Group, 2011)In this book, Kinnaman argues that young people are leaving the church not because they won't listen or aren’t trying to fathom what the church has to say; actually, quite the opposite is true: a large majority of young people consider themselves spiritual, seeking, or as possessing some sort of faith. However, at some point the message the church is sending doesn’t add up with what they are experiencing in the rest of their lives. As a result, we’re losing them, not just figuratively.

You might recognize Kinnaman as President of The Barna Group and the co-author of unChristian, a book which looked at how nonbelievers view Christianity, and why they're turned off from it. Working on unChristian propelled Kinnaman to write You Lost Me, which focuses on the church from the inside out, seeking to explain why young people who have grown up in church are now departing from it, and what older generations of Christians can do to fix the problem.

In You Lost Me, Kinnaman uses certain terms for the different generations in the church. “Mosaics” are today’s teenagers and twenty-somethings, while “Busters,” “Boomers,” and “Elders” are the older generations in the church and the primary audience of his book. Kinnaman stresses that Mosaics live not just in a different culture, but a culture that is discontinually different from the generations before it. He argues that no generation of Christians has lived through a set of cultural changes as profound and lightning-fast as the Mosaic generation. With computers in every pocket, the world is more accessible than ever before. Mosaics have their worldviews shaped not just from family and direct experiences, but from the experiences and opinions of others shared via the web and through other forms of media.

Kinnaman therefore instructs the older generations on six reasons young people leave the church. It’s important to note that Kinnaman isn’t being accusatory here, nor is he trying to suggest every individual church struggles with every issue listed here. These are simply the top six ways Mosaics who leave the Church characterize her.

1.  Overprotective. Meaning: the church has a tendency to fear and demonize everything outside of the church, especially pop culture. Young people see the world less bleakly—they often perceive media icons describing the reality of the human experience better than the church can. There is also a false separation of the sacred and secular, and the problematic desire of the church to insulate young people from culture instead of working with them to shape it.

2.  Shallow. Although Kinnaman acknowledges that many Mosaics find church shallow because they only have a superficial understanding of faith, he has also found that “faith communities convey a lot of information about God rather than disciplining young believers to live deeply in the reality of God… [p]ut the two together and you get a generation of young believers whose faith is an inch deep and a mile wide—too shallow to survive and too broad to make a difference.”