A "rare" book indeed
Pilgrim's Progress is not a "hidden" commentary on the social conditions of Bunyan's time, rather it is a searching story of a dead souls resurrection and journey to Heaven. This book is commonly known in reformist circles. William Mason however is a man with a profound spiritual understanding of the souls resurrection and is well qualified to add his foot “notes”. If Pilgrim's Progress is a favorite, then your soul will be glad to read Mason's notes as well. These “notes” are not randomly scattered comments, but they are almost a second embedded book. Don't hesitate, I've read my copy several times and it's as soul reviving as the first time.