One reason I wrote my new book Center Church: Doing Balanced, Gospel-Centered Ministry in Your City is that I believe there is a common misunderstanding of the relationship between doctrine and ministry.

Let me illustrate. A puzzling but common sight today is that many churches share the same doctrinal foundations, yet go about ministry in radically different ways. For example, consider two Presbyterian churches that both subscribe wholeheartedly to the Westminster Confession of Faith and catechisms. The first church uses contemporary music and very little discernible liturgy, employs lay ministers to lead meetings and ministries as well as pastors, and deploys the latest marketing and media strategies. The second church operates in almost the opposite way, using classical music, traditional liturgy, and emphasis on the ordained clergy. They also vigorously criticize the methods of the other church as a betrayal of the Reformed faith, and perhaps even of the gospel itself.

This article first appeared in edited form on CNN and is printed below in its entirety.

When I was diagnosed with cancer, the question "Why me?" was a natural one. Later, when I survived but others with the same kind of cancer died, I also had to ask, "Why me?"

In my last post, I made an argument for why we still need apologetics. Believing has both a head and a heart aspect, so while some non-Christians will need more help with one than the other, we can’t ignore either one.

So what can we say when we are called upon to present the reasons why we believe?

First, I try to show that it takes faith to doubt Christianity, because any worldview (including secularism or skepticism) is based on assumptions. For example, the person who says, “I can only believe in something if it can be rationally or empirically proven” must realize that that in itself is a statement of faith. This “verification principle” cannot actually be proven rationally or empirically, making it an assertion or a claim, not an argument. Furthermore, there are all sorts of things you can’t prove rationally or empirically. You can’t prove to me that you’re not really a butterfly dreaming you’re a person. (Haven’t you seen The Matrix?) You can't prove most of the things you believe, so at least recognize that you have faith.

Apologetics is an answer to the “why” question after you’ve already given people an answer to the “what” question. The what question, of course, is “What is the gospel?” But when you call people to believe in the gospel and they ask, “Why should I believe that?” —then you need apologetics.

[This was previously posted on Redeemer.com.]

I find it frustrating when I read or hear columnists, pundits, or journalists dismiss Christians as inconsistent because “they pick and choose which of the rules in the Bible to obey.” What I hear most often is “Christians ignore lots of Old Testament texts—about not eating raw meat or pork or shellfish, not executing people for breaking the Sabbath, not wearing garments woven with two kinds of material and so on. Then they condemn homosexuality. Aren’t you just picking and choosing what they want to believe from the Bible?"