“An engaging, lucid, and informative introduction to the teachings and traditions of Catholicism” (Wall Street Journal), from one of America’s most prominent Catholic intellectuals. In this remarkable exploration of the Catholic world, prominent Catholic author and papal biographer George Weigel offers a luminous collection of letters to young Catholics, not-so-young Catholics, and any curious souls who wonder what it means to be Catholic today. Weigel takes readers on an epistolary tour of Catholic landmarks—from Chartres Cathedral to St. Mary's Church in Greenville, South Carolina; from the Holy Sepulcher in Jerusalem to G.K. Chesterton's favorite pub in Oxford; and from the grave of a modern martyr in Warsaw to the Sistine Chapel. This revised and expanded edition includes five new chapters that examine topics at the heart of the modern faith—ranging from the mystery of evil to the puzzle of secularization—and feature sacred sites from Lithuania to Mexico. Weaving together insights from history, literature, theology, and music, Weigel illuminates the beliefs that give Catholicism its distinctive texture and explores the theological importance of grace, prayer, vocation, sin and forgiveness, suffering, and—most importantly—love. To a world that sometimes seems closed and claustrophobic, he suggests, Christian humanism offers a world with windows and doors—and a skylight.