Helping to bring some answers to tough questions.

Click on each below to learn more.

Dr. Richard Knopp

Professor Emeritus of Philosophy & Christian Apologetics at Lincoln Christian University

Dr. Rich Knopp is Professor Emeritus of Philosophy & Christian Apologetics at Lincoln Christian University, where he has taught since 1983. His formal education was done at St. Louis Christian College (BA in Christian Ministry), Lincoln Christian Seminary (MDiv - Philosophy & Theology), Southern Illinois University at Carbondale (MA in Philosophy), and the University of Illinois at Champaign (PhD in Philosophy).

Rich is the Former Program Director of Room For Doubt and the presenter for Room For Doubt's seminars and workshops at conventions, conferences, colleges, Christian camps, and churches. He provides and manages the content on the R4D website and mobile app and writes the scripts for the program's videos.

He also serves as the Director of WorldViewEyes, a youth-oriented program launched in 2000 that has received five grants from the Lilly Endowment totaling over $1,000,000. It helps youth understand different worldviews and challenges them to live a consistently-applied Christian worldview. He has written and produced the program's multimedia presentations that have been attended by about 80,000 youth and adults in 22 states, Canada, and China.

His particular interest is the relationship between science and the Christian faith. He was a $10,000 award winner from the Templeton Foundation for developing an integrative seminary course in science and religion. His most recent work is Truth about God: What Can We Know and How Can We Know It? (2021). In addition, Rich has articles in four journals, chapters on Christianity and science in two books (Taking Every Thought Captive and Theology in the Present Age), a chapter on Christian ethics in I Am Put Here for a Defense of the Gospel, and a chapter on philosophy of science in relation to the Stone-Campbell religious tradition in Restoration and Philosophy. (For links, go to

Rich has delivered special lectureships or multimedia presentations at a number of popular and professional conferences, including the North American Christian Convention; the International Conference on Missions, The Stone-Campbell Journal Conference; the Association of College Ministries, the Midwest and National Evangelical Theological and Philosophical Society Conferences; the Wheaton Theology Conference; and the Center for Research in Science at Azusa Pacific University. He also serves on the board for the Christian Campus Foundation (Axiom), a campus ministry at the University of Illinois in Urbana-Champaign.

Rich and his wife, Paula, have three married children and seven grandchildren. He has traveled to England, France, Italy, New Zealand, Fiji, Australia, Jamaica, Greece, Turkey, and China. He was a gifted athlete who was a high school all-state second baseman in North Carolina and played for a AAA State Champion baseball team. In 2013, he was inducted into the inaugural class of the Athletic Hall of Fame for basketball at St. Louis Christian College where he held the all-time scoring record (2,225 pts.) for about 20 years. He is still second on their all-time scoring list, second in average pts/game (22.7), and first in free throws made (515).

Dr. Zach Breitenbach

Associate Director & Adjunct Prof at Lincoln Christian University

Dr. Zach Breitenbach is the Associate Director of Room For Doubt and an adjunct professor at Lincoln Christian University (LCU).

Zach graduated with a BS in Computer Science from North Carolina State University, where he was Valedictorian, graduating with a 4.0 GPA. While at NC State, he also earned Academic All-American honors three times as an NCAA Division I college wrestler. Zach earned his MBA at NC State and worked for American Airlines in Dallas as a contract negotiator.

With a passion for Christian apologetics, Zach was led to the Seminary at Lincoln Christian University. He taught undergraduate courses in business and theology and received an MA in Christian Apologetics with highest honors.

For several years after graduating from Lincoln, Zach taught New Testament, Apologetics, and World Religions to high school students at Northside Christian School in St. Petersburg, Florida, where he also served as wrestling coach.

In 2019, he completed a PhD in Theology & Apologetics from Liberty University and became the Room For Doubt Assistant Director. He has published articles in the Journal of the Evangelical Theological Society, Philosophia Christi, Southeastern Theological Review, Journal of the International Society of Christian Apologetics, Themelios, and Irish Theological Quarterly. In 2021, he published the book, Slipping Through the Cracks: Are Some Lost Who Would Have Been Saved in Different Circumstances?

Zach grew up in Cincinnati, Ohio, and has traveled to China, Japan, Ireland, Germany, Greece, New Zealand, Hawaii, Haiti, Israel, Italy, and more. His hobbies include Bible study, listening to podcasts, playing games with friends and family, coaching wrestling, and watching sports.

He has been a regular contributor to the R4D website since 2015.

Hannah Brimner

Technology Specialist

Hannah Brimner is the Technology Specialist for Room For Doubt. She creatively enhances the website and the mobile app, contributes frequently to our social media, helps with video and animation production, and designs page layouts for print and digital materials. Hannah is a graduate of Lincoln Christian University and Seminary (B.A. in Christian Ministry and M.A. in Ministry).

Mark Mittelberg

International speaker, Best-Selling Author

Mark Mittelberg is an international speaker and the bestselling author of The Questions Christians Hope No One Will Ask (With Answers), Confident Faith, and The Reason Why Faith Makes Sense. He is also the primary author of the celebrated Becoming a Contagious Christian training course (with Lee Strobel and Bill Hybels), which has been translated into more than 20 languages and helped more than 1,500,000 people around the world learn to share their faith in natural ways. Mark was the original outreach director at Willow Creek Community Church in Chicago, where he served for many years. He now writes, speaks, and consults from Denver, Colorado, where he lives with his wife, Heidi.

Lee Strobel

Best-Selling Author and Professor of Christian Thought, Houston Baptist University

Atheist-turned-Christian Lee Strobel, former award-winning legal editor of The Chicago Tribune, is a New York Times best-selling author of more than twenty books and serves as Professor of Christian Thought at Houston Baptist University. Described in the Washington Post as “one of the evangelical community's most popular apologists,” Lee won Gold Medallions for The Case for Christ, The Case for Faith, and The Case for a Creator, and shared the Christian Book of the Year award with Garry Poole. Lee was educated at the University of Missouri (Bachelor of Journalism) and Yale Law School (Master of Studies in Law). His son Kyle is a theology professor and his daughter Alison teaches at a Christian school.

Garry Poole

Curriculum Specialist

Garry Poole created the adult and youth discussion guides for the "Big Questions" series, and he hosted and produced the videos of the “Doubters Uncensored” panel. Garry is a curriculum specialist who has written the discussion guides for many of Lee Strobel’s best-selling books, like The Case for Faith, The Case for Christ, and The Case for a Creator. His publications also include Seeker Small Groups and The Complete Book of Questions: 1001 Conversation Starters for Any Occasion

Daniel McCoy

Editorial Director for Renew

Daniel is the Editorial Director for Renew, a collaborative network that focuses on disciple-making (see He has a bachelor’s degree in theology (Ozark Christian College), an MA in apologetics with a focus on atheism (Veritas International University), and a PhD in theology with a focus on Buddhism (North-West University, South Africa). He co-authored The Atheist’s Fatal Flaw with Norman Geisler (Baker, 2014). He plays guitar and piano and occasionally enjoys writing his own songs.

Tracy Thomas

Director of Alumni Relations, Lincoln Christian University

Tracy attended LCU to become a high school English teacher, but God closed that door and opened new doors in youth ministry. He served in youth ministry for 18 years at three different churches and served as the preaching minister for 10 years at Woodlawn Christian Church in Woodlawn, IL. He has led two different churches in Room For Doubt’s six-week series called “Basic Questions.” He is now the Director of Alumni Relations at Lincoln Christian University. Tracy is married to Lori. They have two amazing daughters, Katie and Hannah.

Alison DeLong

Teacher, Covenant Christian School, Conroe, TX

Alison DeLong teaches at Covenant Christian School in Conroe, Texas. Her classes include U.S. History, World History, and Christian Character & Leadership. She has a B.A. in Philosophy from Lincoln Christian University and an M.A. in Christian Cultural Apologetics from Houston Baptist University. Her graduate work focused on the integration of rational and imaginative apologetics and how we can analyze and contribute to culture from a Christian worldview. She was honored with the Outstanding Student in Apologetics Award at HBU.