Pilgrim's Progress definitely qualifies as a book that every person who calls himself a Christian should read. The preacher Charles Spurgeon is reported to have read Pilgrim's Progress 100 times! Spurgeon said he suspected that if John Bunyan were to be poked, he would bleed scripture. The story is a wonderful allegory which richly illustrates deep biblical truths, and Bunyan's knowledge and understanding of the Bible is evident as he weaves so many ideas and terms from the Bible throughout his story.
Bunyan's goal in writing Pilgrim's Progress was to present Christian doctrine and truths in a way that was entertaining and memorable so it would be easily understood and remembered by the average layperson. Bunyan gives his metaphorical characters and places self-descriptive names - Worldly Wiseman, Evangelist, Faithful, Atheist, Doubting Castle, Celestial City, - so his meaning is clearly conveyed to the reader. His descriptions and use of symbolism create a lasting impression in the reader's mind. He has a way of taking an idea from Scripture and graphically bringing it to life.
A few ideas are repeated throughout the story that communicate spiritual truths clearly taught in the Bible. Probably the most prevalent and important theme is that there is only one right path - one way to heaven. Every time Christian strays from this path, he gets himself into trouble. Another truth which comes through is that the journey to heaven (the Christian life) is not an easy one. Bunyan's story reminds the Christian reader that he will certainly face various temptations, obstacles, distractions, and difficulties throughout life. Bunyan also shows in his story that God always provides instruction, help and comfort along the way, through his Word and through His people.
As the characters share their experiences and discuss various issues along the journey, Bunyan uses their dialogue to communicate rich truths to the reader, almost like mini sermons. Anyone who isn't a Christian or is unfamiliar with the Bible can enjoy and profit from reading Pilgrim's Progress, but it definitely holds more meaning and instruction for the Christian reader.
(for my more thorough discussion of Pilgrim's Progress, visit my blog at www.ImAllBooked.com)