John F. MacArthur, Jr. (born June 19, 1939) is a pastor and author known for his internationally syndicated radio program Grace to You. He has been the pastor-teacher of Grace Community Church in Los Angeles, Ca since February 9, 1969. Theologically, MacArthur is considered a Calvinist, and a strong proponent of expository preaching. He has authored or edited more than 150 books, most notably the MacArthur Study Bible, which has sold more than 1 million copies (Gold Medallion Book Award).
Aiden Wilson Tozer (1897 –1963) was an American Christian pastor, preacher, author, magazine editor, and spiritual mentor. 44 years of ministry, associated with the Christian and Missionary Alliance (CMA), a Protestant Evangelical denomination. Among the more than 60 books that bear his name, at least two are regarded as Christian classics: The Pursuit of God and The Knowledge of the Holy. His books impress on the reader the possibility and necessity for a deeper relationship with God.