Stephen Um (PhD, University of St. Andrews) serves as the senior minister of Citylife Church in Boston, Massachusetts. He also serves as a council member for the Gospel Coalition. Stephen lives in Boston, Massachusetts, with his wife, Kathleen, and their three daughters. R. Kent Hughes (DMin, Trinity Evangelical Divinity School) is senior pastor emeritus of College Church in Wheaton, Illinois, and visiting 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 serves as 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.