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. C. J. Mahaney is the senior pastor of Sovereign Grace Church of Louisville. He has written, edited and contributed to numerous books, including Proclaiming a Cross-Centered Theology; Don't Waste Your Sports; and Sex, Romance and the Glory of God. C. J. and his wife, Carolyn, are the parents of three married daughters and one son, and the happy grandparents to twelve grandchildren.