How can Christians properly celebrate Christmas today? Certainly, Christmas trees, gift-giving, family reunions, and many other customs can all be joyful traditions of the season. But Spurgeon would say that the primary way to celebrate Christmas is by faith in the incarnate, crucified, and risen Savior. That’s why A Wondrous Mystery exists: amid a busy holiday season, it is meant to be a daily reminder of why we celebrate—that “the Infinite has become an infant” and “the joy of his coming is still in our hearts.” Thirty daily devotions to help keep your heart focused on Christ in the busy holiday season. First book in the Old Made New series, making the teaching of theologians and pastors who have left us a rich heritage of faith accessible for modern-day readers. Compiled by Geoffrey Chang, curator of the Spurgeon Library at Midwestern Baptist Theological Seminary.