The focus of this book is on people who changed, influenced, or brought larger audiences to Christian music, whether it is music used during a worship service or to the broader public. It is not a musical history, but rather an historical one. It includes indivduals from the earliest days of the church (St. Gregory the Great, St. Benedict of Nursia) to today (Johnny Cash, the Gaithers). Being a musician is not an absolute criteria for making this list. Billy Graham makes the list, for example, because his Billy Graham Crusades exposed Gospel music to millions of people - or tens of millions of people - who may never had heard Gospel music before. The biographies of the individuals contained within are not meant to be a complete examination of the lives and careers of the people involved, but rather are intended to provide basic background information, especially in the tables. The text below the tables is limited to a discussion of why the individual had an impact on the music of Christianity. Also, many of the composers, musicians and vocalists in the list also produced secular music. Only their Christian music was considered for inclusion and positioning in the Top 25. So, for example, the fact that Mozart is #16 is not a comment on his overall place in the history of music, but rather a position based on his output of religious music.