Relations between evangelicals and Catholics have become richer and more nuanced in recent years. Groups such as Evangelicals and Catholics Together emphasize commonalities. High-profile evangelicals such as Francis Beckwith convert to Catholicism, while large numbers of Catholics continue to embrace evangelical faith, which itself has shown a growing fondness for Catholic forms, thought, and history.

Chris Castaldo, pastor of outreach at College Church in Wheaton, Illinois, understands the nuances better than most. Raised on Long Island, Castaldo was a full-time fund-raiser for the Catholic Church. Now he is the author of Holy Ground: Walking with Jesus as a Former Catholic (Zondervan, 2009).

Chris, you come from a Catholic family and used to raise funds for the Roman CatholicChurch. Now you're a pastor in a large suburban church in Wheaton, Illinois, the "evangelical Vatican." How did you get from there to here?

I tend to see myself as a modern-day Mr. Magoo: not particularly clever or intentional, but, despite myself, guided by divine oversight. Memories of my childhood parish are positive. Father Tom was (and is) a great pastor who loved us deeply. Then I embraced evangelical faith.

While working in the Catholic Church, I drank a lot of coffee with priests—Jesuits, really smart ones. We'd debate theology and they'd hand me my head, nicely of course. Frustrated by my inability to articulate an answer for my faith, I went on to do ten years of theological study between Bible college, seminary, and grad school, and since 2003 I've served as the pastor of outreach at College Church in Wheaton. As a result, I can say with confidence that I'm not Catholic! However, just because I now disagree with Catholic doctrine doesn't mean I can't love Catholics and continue to learn from them.

Why did you write Holy Ground?

It is mostly an outgrowth of my ministry at College Church. Several years ago I noticed that some people in our community were approaching Catholic friends in one of two ways: either attacking them like foaming-at-the-mouth pit bulls, or with such open-mindedness that their brains seemed to have fallen out of their heads. Therefore, I taught a class entitled "Perspective on Catholicism" intended to bring a more biblically informed balance. With John 1:14 as our model, the class sought to emphasize the need to follow after Jesus' example of "grace and truth." The material eventually became a manuscript and, thanks to Zondervan, Holy Ground was born.

What has been the response from Catholics?

So far it's been positive. Most of them seem to realize that Holy Ground is a pastoral work intended to bring understanding and healing, not an invective or diatribe. I had Catholic authors, scholars, and laypeople reading the manuscript from the very beginning to ensure that its propositions are not only accurate but also convey genuine courtesy and respect.

It seems that many evangelicals are heading "back to Rome," headlined by Frank Beckwith. How significant is this trend?

Frank Beckwith has become a friend. When we cooperated in Wheaton College's Penner Forum on September 3, folks lined up to say hello and give us the privilege of signing our respective books for them. It was hilarious. Frank and I were standing directly beside one another when Catholics on his line testified to how God had led them "home to the Church," while just six inches away people explained to me how God had "saved them from their Catholic background." Based on the size of Frank's line, I'd say that the movement is significant, although I don't think it's nearly as large as the migration that's going in the opposite direction.

Why do you think this is happening, and what lessons do you think we evangelicals should be taking from it?

I see four reasons why Protestants swim the Tiber, that is, move toward the Catholic Church: a deeper expression of reverence, perceived unanimity in regard to authority, a traditionally rooted liturgy, and a more robust moral theology. There are of course entire books written on how evangelicals should learn from Catholics in each of these areas. I would agree that there are some important lessons for us to learn.

At the same time, evangelical churches have often grown by adding members from Roman Catholic backgrounds. Why do most Catholics who switch do so?

From my research and personal experience it comes down to religious authority. Where is the proximate authority for Christian faith: the magisterium or the text of Scripture? The first half of Holy Ground unpacks this question by explicating five popular reasons why Catholics make the switch: ministry calling for laypeople, relationship with Jesus over rule-keeping, direct access to God, Christ-centered devotion, and grace over guilt as the proper motivation for obedience.

Do you think evangelicals should actively seek to evangelize Catholics?

Absolutely! And I also think that evangelicals must regularly evangelize evangelicals, and, for that matter, I must constantly evangelize myself. In other words, we need to reflect upon the gospel beyond the point of our personal conversion; every day I must remind myself of Jesus' death and resurrection and who I am in light of that. Since man looks only on the outward appearance and the Lord looks at the human heart, I don't presume to know the nature of my Catholic friend's faith. Yet, precisely because I'm an evangelical—a person whose life is dedicated to embodying and proclaiming Jesus, the Evangel—I'm committed to evangelism, even among Catholic friends and loved ones.

In your book you describe different kinds of Catholics. What are they, and why is this information important in reaching out?

There is often a vast difference between the propositions of our catechisms and the beliefs of people who fill our pews. This is true of course on both sides of the Catholic/Protestant divide. Accordingly, Holy Ground posits three sorts of Catholics one is likely to meet in America today: the Traditional, the Evangelical, and the Cultural. These terms are imperfect. For instance, "Evangelical Catholic" is problematic since Catholics deny the doctrine of faith alone. However, these are the words that seem to be most commonly used. In a nutshell, the "Traditional" is the Vatican I variety, "Evangelical" is Vatican II, and "Cultural" is the nominal or cafeteria Catholic. Each profile is defined by the particular form of religious authority on which one builds his or her faith. Connecting the dots between these people and their primary form of authority is critical for properly contextualizing the gospel message.

Catholics and evangelicals have a lot in common theologically. The participants in Evangelicals and Catholics Together emphasize those commonalities. Yet some key differences remain. What are they?

Here is how I see it: Catholics and Protestants virtually agree on what theologians call the "objective" dimensions of faith, that is, divine redemption, which comes to us in and through Jesus. Where we differ is on how that salvation is mediated to humanity. Does it come through the sacraments of the One, Holy, Catholic, Apostolic Church, as Rome asserts? Or is it supremely revealed in Scripture and accessed by faith alone, as Protestants believe? Like two sets of dominos running parallel before proceeding in divergent directions, this difference causes Catholic and Protestant faith to differ significantly on issues of justification, worship, and practical Christian ministry.

Mark Noll famously asked whether the Reformation is over. Is it?

Probably not. Noll and Carolyn Nystrom's book titled Is the Reformation Over? offers a helpful survey of how Catholics and evangelicals have related to one another through the years, particularly over the last half-century. I told Carolyn Nystrom over lunch recently that she and Dr. Noll did a good job of explaining how evangelicals on the whole have improved in understanding and relating to Catholics. However, that there remain profound differences of belief and practice between Catholics and Protestants is undeniable.

Does it matter whether one follows Christ in a Catholic church or an evangelical church? How would you counsel a Catholic who has recently received Christ as Savior and Lord?

I'm an evangelical Protestant for a reason. We evangelicals have a lot of faults, many of which not only require correction but also repentance. Yet, I believe the Protestant Reformers had it right in their assertion of Scripture alone and faith alone, and that Catholicism had it wrong for opposing these ideas. Therefore, yes, I think it does matter where one follows Christ. My counsel to a Catholic who recently received Christ, presumably in an evangelical Protestant sort of way, would be to read Scripture, dialogue with your priest, meet with pastors from local evangelical churches, pray a lot, and let the decision of where you'll be a church member be a process that's informed by godly people who take the Bible seriously. I think we need to trust that God cares about such decisions and is faithful to lead us by his grace.

What do you see ahead in evangelical and Catholic relations at the local church level? Do you see our differences blurring, or sharpening?

It's an exciting time to ask this question. On the one hand, Pope John Paul II's "New Evangelization" has spawned a form of neo-Catholicism that appears rather traditional. Examples of this are Relevant Radio or many of the programs on EWTN Global Catholic Network. On the other hand, there is the so called "New Calvinism" burgeoning among many evangelical Protestants, a movement that takes seriously Reformed theology and its application to life. As these communities intersect, I expect to see a sharpening of differences, more seriousness toward truth, and I hope a greater measure of Christ-centered courtesy and respect.

Stan Guthrie is a member of College Church and a Christianity Today editor at large. This Q&A is also available on Guthrie's website, www.stanguthrie.com.

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