The Holy War made by Shaddai upon Diabolus, for the Regaining the Metropolis of the World; Or, The losing and taking again of the Town of Man-soul.

The Holy War is a short novel (approximately 200 pages), written as an allegory by John Bunyan. While not as famous as his earlier allegory, Pilgrim's Progress, I found it nearly as valuable.
The story is structured around one Town of Mansoul. This town, built perfectly, bears the image of it's builder, King Shaddai (Almighty). Now a rebellious servant of this King, by the name of Diabolus, was disowned and dismissed from the King. This Diabolus in revenge, goes to Mansoul and through deceit, gains entry to their town by convincing them to overthrow the rule of Shaddai. Once inside, he distorts the town from it's former semblance, for he mutilates the image of the King and sets up his own image. He also causes the eyes of the mayor of the town (Understanding), who had permitted his entrance, not to see the light. The recorder (Conscience), he also causes to sin, making him a madman, at times sinning and at other times condemning sin of the city. Also the allegiance of Lord Willbewill changed from one that did righteousness, to one who serves Diabolus.
Because of the fall of these three men, the voluntary surrender of Mansoul to Shaddai is impossible. Besides, Diabolus strengthened his stronghold in the city by bring into it all manners of Diabolians (sin), who pollute the city. He also fortifies the Eye-Gate and Ear-Gate, so that enemy penetration will be made even more difficult.
Despite this treachery Shaddai's son, Emmanuel, takes a vow to restore the City for the Glory of his Father.
To tell much more could reduce your desire to read the book, which would be antithetical to my goal. Suffice it to say, The Holy War is a brilliant exposition of many intricate doctrines. Mainly, the fall, conversion, salvation, and perseverance of the soul, not to mention, fellowship with God, the discipline of God in the life of a believer, and sanctification. The list could go on but my explanation of the book will not compare to you going and reading it, for indeed this book review is merely scratching the surface of this magnificent parable.
You can find the entire book online, here. http://acacia.pair.com/Acacia.John.Bunyan/Sermons.Allegories/The.Holy.War/index.html