Robertson McQuilkin is a speaker and writer, engaging in extensive conference ministry in the United States and overseas. He served as the third president of Columbia International University for 22 years, and is now president emeritus. Before becoming president, McQuilkin was headmaster of Ben Lippen School and a missionary in Japan. A few of his other books include Five Smooth Stones (Broadman), Life in the Spirit (LifeWay) and Introdution to Biblical Ethics (Tyndale).
Philip Yancey is a journalist and writer who writes a featured column in Christianity Today. The author of more than a dozen books. He is the recipient of a Christianity Today Book of the Year Award, two ECPA Book of the Year Awards, and eleven Gold Medallions. He lives in Evergreen, Colorado.