Mark Dever (PhD, Cambridge University) is the senior pastor of Capitol Hill Baptist Church in Washington, DC, and president of 9Marks (9Marks.org). Dever has authored over a dozen books and speaks at conferences nationwide. John MacArthur is the pastor-teacher of Grace Community Church in Sun Valley, California, where he has served since 1969. He is known around the world for his verse-by-verse expository preaching and his pulpit ministry via his daily radio program, Grace to You. He has also written or edited nearly four hundred books and study guides. MacArthur serves as the president of the Master's College and Seminary. He and his wife, Patricia, live in Southern California and have four grown children.