How a mega-church founder rediscovered religion

Rob Bell

FORTUNE – Most successful religious leaders have also had a solid business mind. All institutions, spiritual or otherwise, need revenue to survive. They must also, argues Rob Bell, meet the needs of their constituents.

Bell is an evangelical Christian who, at the age of 28, founded the Mars Hill Bible mega-church in Michigan after his Christian rock band, Big Fil, folded. In 2011, he published the book Love Wins: A Book About Heaven, Hell, and the Fate of Every Person Who Ever Lived, which advocates for a loving Christian church. In it, Bell questions the existence of hell. His uncertainty polarized his followers and the greater Christian community. Since its publication, Bell has left Mars Hill and has moved to California to work on a television project.

This year, he published a new book called What We Talk About When We Talk About God. Bell spoke with Fortune about innovation in religion and the business quirks of the “church world.”

Fortune: How did it all start?

Rob Bell: I started out in a band. I had grown up in church, so when the band broke up and I needed to figure out what to do with my life, I just had this sense of, “Man, church could be done better.”

MORE: This incredible face is the future of tech

So I went to seminary and studied to be a preacher. Then at 28, my wife and some friends started a church. It got massive really fast. I didn’t have any training in leadership.  As far as resources, vision, strategy, budgeting, I was still sort of in band mode. Like, how do you create an awesome experience for people?

What did you learn as a bandleader that you brought to church?

When you’re in a band, if you haven’t engaged people, they just walk out and have a smoke. That’s how I cut my teeth. You want to win over the whole room, and it better be great.

But then I got into church world and realized people went to church on Sundays because you’re supposed to, or else something bad will happen. That was a foreign impulse. In the rest of your life, you don’t go do things because you’re just supposed to. So I sort of approached the whole thing with, “This should be great, this should be really compelling.”  It doesn’t mean it always has to be noisy — it might be really still and reflective. It might be joyous and exuberant. It might be challenging and demanding. It might be deeply ambiguous and filled with doubt and pain and sorrow and beating your chest and shaking your fist at the heavens, but it would at least be alive. And it would at least reflect what life was really like.

Can you focus on the parts that you love and effectively run a church?

I’ve had leaders say, “Well that’s nice, I’d love to organize my whole thing about what I love to do,” to which I respond, “OK …”

If the CEO is spending 25% of her time in the area where she’s really wired to contribute, but 75% of her time, she’s just grunting it out, she’s going to burn out quite quickly. Because there’s somebody else where that 75% will turn them on like crazy.

Why, do you think, are leaders afraid to do what they love?

Sometimes it’s ego. Sometimes it’s  power and control. Sometimes people think, “Maybe I won’t get the type of credit that I deserve if other leaders take over,” and it’s not true. You’ll be so happy, you won’t care.

What are some differences between the business world and your world?

First off, when there’s a bottom line, that’s a very straightforward way to evaluate. In church world, some of the evaluation is a bit murkier. There’s a management dimension to this and then there’s a mystical dimension to this. For example, sometimes what’s really important for the vibrancy of the church is that you take a risk any businessperson would say is crazy. At Mars Hill, we started giving away 25% of the offerings from the first Sunday.

MORE: China and Russia: Best frenemies forever?

Part of the difference between business leaders and a church is that when a church becomes solely focused on its own self-preservation, it has, in that moment, begun to die.

Why do some churches and followers have trouble letting go of the threat of hell as a reason for doing things?

Well first off, let me say a positive: Our actions in the world do have consequences, and our choices can lead us to all sorts of misery. We see spousal abuse, we see drug addiction, we see people upside-down in all sorts of really horrific ways. Part of the spiritual life is heightening the urgency of the decisions that we make today.

Secondly, it’s probably rooted in where people are developmentally. If you can clearly articulate who the enemy is, that’s really powerful. Sometimes people are at that stage. For example, a hard-core drug addict who has had a rebirth experience generally needs a lot of structure.

Other times, it becomes an excuse not to think for yourself, and then it works against people’s health. If you look historically, a cult leader is really just an exaggerated form of the impulse that says, “Tell you what, I’ll take care of the thinking here.” That can be terribly attractive.

Do you think organized religion is a troubled institution?

It seems that institutions in our culture, across the board, are upside-down for a lot of people. They always need to be reformed, and that’s what we’re seeing now. I think it’s really important to point out that the innovation out there right now is just extraordinary.

So the church is like any other institution, full of great and terrible things?

That’s it. It’s all there. Whatever you look for, you can find.

Subscribe to Well Adjusted, our newsletter full of simple strategies to work smarter and live better, from the Fortune Well team. Sign up today.