John Hall (1806-1894), who edited the Letters of J.W. Alexander, is the author of book-length (100+ pages each) expositions of the first two questions and answers of the Westminster Shorter Catechism: The Chief End of Man: An Exposition of the First Answer of the Shorter Catechism (1841), and The Scriptures the Only Rule of Faith: An Exposition of the Second Answer of the Shorter Catechism (1844). To help us understand, from the Scriptures, what is our purpose in life, and what is the rule of our faith and practice, is the aim of these first portions of our Catechism, and Hall expounds these questions and answers in-depth. These volumes are intended for young as well as old, and they are an encouragement to all who read them with the heart of a child. Both of these works have been reprinted by Solid Ground Christian Books, the former with an essay on the Shorter Catechism by B.B. Warfield. They are spiritual gems, and worth downloading for prayerful study and application.