The Pilgrim's Progess

 is a book in Deus Ex: Invisible War. It is a excerpt from a longer work of the same name written by John Bunyan. The is a highly regarded Christian allegory.

Transcript
The Pilgrim's Progress by John Bunyan

''... I turned my head to look back and saw Ignorance come up to the River side: but he soon got over... For it happened, that there was then in that place one Vain-hope a ferry-man... When he was come up to the Gate he looked up to the writing that was above, and then began to knock, supposing that entrance should have been quickly adminstered [sic] to him... [But The King] commanded the two Shining Ones... to go out and take Ignorance and bind him hand and foot, and have him away. Then they took him up, and carried him through the air to the door that I saw in the side of the hill, and put him in there. Then I saw that there was a way to Hell, even from the Gates of Heaven, as well as from the City of Destruction.''