Our group has been well-served by choosing books with short chapters that can be read and discussed in one meeting. When each chapter stands on its own, newcomers and folks who have been away can return and and not be lost because of what they've missed. So our current book is 131 Christians Everyone Should Know, from the editors of Christian History magazine, with a forward by J.I. Packer. It covers famous Christians from various walks of life: theologians, evangelists, preachers, musicians, artists, writers, denominational founders, political leaders, scientists and more. Each biography is just two to three pages long, and we won't do all 131 chapters, as that would take the better part of three years! Instead we'll focus on one chapter each week through the summer, then switch to something else in September.
You may be able to find the book at Logos or another local Christian bookstore, or purchase it from Amazon HERE.