Richard B. Gaffin, Jr. is Professor Emeritus of Biblical and Systematic Theology at Westminster Theological Seminary in Philadelphia. He is a graduate of Calvin College, Grand Rapids, and he holds his ThM and ThD degrees from Westminster. He is the author of Resurrection and Redemption: A Study in Paul's Soteriology, and Perspectives on Pentecost.

J. Gresham Machen (1881-1937) was a professor at Princeton Seminary. He founded Westminster Seminary in 1929, and led the formation of the Orthodox Presbyterian Church in 1936. His books include Christianity & Liberalism, The Christian View of Man and The Person of Christ.



Peter Lillback (PhD, Westminster Theological Seminary) is president and professor of historical theology and church history at Westminster Theological Seminary. He also serves as the president emeritus and founder of The Providence Forum and senior editor of the new Unio cum Christo: An International Journal of Reformed Theology and Life.


Bernard Aubert (PhD, Westminster Theological Seminary) is Managing Editor of Unio cum Christo—an international journal based at Westminster Theological Seminary, Philadelphia, and International Reformed Evangelical Seminary, Jakarta—and a visiting lecturer in New Testament studies at Farel Faculté de Théologie Réformée, Montréal, Canada. He studied theology at the Faculté Jean Calvin, Aix-en-Provence, and then completed a PhD in hermeneutics and New Testament at Westminster Theological Seminary, Philadelphia. He is the author of The Shepherd-Flock Motif in the Miletus Discourse (Acts 20:17–38) Against Its Historical Background (Peter Lang, 2009), and a contributor to Thy Word Is Still Truth: Essential Writings on the Doctrine of Scripture from the Reformation to Today (P&R Publishing, 2013). He is married to Annette, and they have one son: Pascal.

K. Scott Oliphint is Professor of Apologetics and Systematics at Westminster Theological Seminary and ordained in the Orthodox Presbyterian Church. He is a regular contributor to He received his MAR, ThM, and PhD from Westminster Theological Seminary. He has written numerous journal articles in the field of apologetics and has written several books on the topic.
J.H. Bavinck (1895–1964) was an internationally admired pastor, missionary, theologian, and apologist. A nephew of famed dogmatician Herman Bavinck, he studied at the Vrije Universiteit in Amsterdam and then in Gießen and Erlangen, Germany before ministering in the Netherlands and in Indonesia. He went on to serve as professor at the Vrije Universiteit then at Kampen. He wrote widely on the theology of missions and elenctics.

John Murray (1898-1975) was born in Scotland. He taught Systematic Theology at Westminster Theological Seminary for more than 30 years. A widely-celebrated theologian, his books include Redemption: Accomplished and Applied and Epistle to the Romans.




William Edgar is Professor of Apologetics and John Boyer Chair of Evangelism and Culture at Westminster Theological Seminary. William is also an Associate Professor at the Faculté Jean Calvin. He received his MDiv from Westminster Theological Seminary and a DTheol from the University of Geneva. William and his wife, Barbara, have two children and three grandchildren.


R. Kent Hughes (DMin, Trinity Evangelical Divinity School) is senior pastor emeritus of College Church in Wheaton, Illinois, and recently retired as professor of practical theology at Westminster Theological Seminary in Philadelphia, Pennsylvania. Hughes is also a founder of the Charles Simeon Trust, which conducts expository preaching conferences throughout North America and worldwide.He is the series editor for the Preaching the Word commentary series and is the author or coauthor of many books. He and his wife, Barbara, live in Wyncote, Pennsylvania, and have four children and an ever-increasing number of grandchildren.

Dr. Alfred Poirier (DMin, Westminster Theological Seminary) is visiting professor of pastoral theology at Westminster Theological Seminary. Dr. Poirier has held a number of additional teaching positions and has also served as a pastor at Rocky Mountain Community Church (PCA) in Billings, Montana for 26 years. Dr. Poirier’s academic interests lie in the areas of pastoral counseling and expository preaching. He is the author of The Peacemaking Pastor (Baker, 2006), and Words that Cut: Learning to Take Criticism in Light of the Gospel (Peacemaker Ministries) and several articles in The Journal of Biblical Counseling.  Dr. Poirier has been married to his wife, Trudy, for 41 years and together they have 3 children: Sarah Clark, Sonja Stordahl, and Anya Valeriano; and ten grandchildren.

John Witherspoon (1723-1794) was born in Scotland and ministered to two congregations there, Beith and in Paisley, before accepting an appointment as president of the College of New Jersey (later Princeton University) in 1768. Remembered today as the only clergyman to sign the Declaration of Independence, Witherspoon was perhaps best known in his defense of Reformed theology and pastoral emphasis on saving faith–as seen in his two popular theological works reprinted here.

Kevin DeYoung is senior pastor at Christ Covenant Church in Matthews, North Carolina, board chairman of The Gospel Coalition, and associate professor of systematic theology at Reformed Theological Seminary in Charlotte. He is the author of The Religious Formation of John Witherspoon, in addition to many popular books, including Men and Women in the Church and Taking God at His Word. He and his wife, Trisha, have nine children.

Thomas Witherow (1824–1890) was born in Ballycastle in the north of Ireland, where he ministered and taught for 45 years. After pastoring a Presbyterian church in Maghera for two decades, he became professor of church history and pastoral theology at Magee College in Londonderry, where he served until his untimely death at the age of 65. Witherow wrote prolifically and on a variety of topics, but he remains best known for his defense of Presbyterian beliefs.

Jonathan Gibson (PhD, University of Cambridge) is associate professor of Old Testament at Westminster Theological Seminary, and an ordained minister in the International Presbyterian Church, UK. He is the author and editor of several books, including two collections of liturgies for corporate and individual worship: Reformation Worship and Be Thou My Vision. Jonny is married to Jackie, and they have four children: Benjamin, Leila, Zachary, and Hannah.

Stephen M. Coleman (PhD, The Catholic University of America) is assistant professor of Old Testament and biblical languages at Westminster Theological Seminary, co-editor of the Westminster Theological Journal, and senior research fellow at the J. Alan Groves Center for Advanced Biblical Research. A graduate of Grove City College (BA, 2002), Westminster Seminary California (MDiv, 2005), and The Catholic University of America (MA, 2010/PhD, 2016), he previously served as associate pastor at Wallace Presbyterian Church in College Park, Maryland (2008–2017) and Assistant Pastor of Valley Presbyterian Church in North Hills, California (2005–2008).


Todd M.Rester (PhD, Calvin Theological Seminary) is associate professor of church history at Westminster Theological Seminary. Dr. Rester is a post-doctoral research fellow at Queen’s University Belfast (September 2016–present). During his time as a research fellow at Queen’s University Belfast, Dr. Rester has served the institution as a guest lecturer in the Master of Arts, History of Religion department as well as various undergraduate history courses. In addition to his time at Queen’s University Belfast, Dr. Rester has taught as an adjunct professor at Puritan Reformed Theological Seminary (2010–2016), Kuyper College (2013–2015), and Calvin Theological Seminary (2011–2015). He also works as a translator for the Dutch Reformed Translation Society (2009–present). Dr. Rester’s academic interests include but are not limited to: the history of the doctrine of Scripture and its reception; early modern and Enlightenment conflicts between theology and philosophy on general and special revelation; and early modern and post-Enlightenment models of missiology.


Herman Bavinck (1854-1921) succeeded Abraham Kuyper as Professor of Theology at the Free University of Amsterdam. With the recent translation into English of his four-volume Reformed Dogmatics there has been a renewed appreciation for this deeply intelligent mind committed to the importance of the church.