The Adventures of Bonnie Day was a book, written by Nathan Rahl. The book was used to subtly teach young men with the Gift certain lessons about life through the adventures of the main characters, Bonnie, Jessup, and Geraldine. It was also a primer to Prophecy. The book was written in many different languages that were found in the Wizard's Keep. Richard Rahl was the only surviving wizard who had received the book, as all the others had been killed.
The Adventures of Bonnie Day was given to Richard Rahl by his foster father George Cypher as a gift for learning to read. Richard felt that the heroes did many ill considered things that were to be learned from so as not to be repeated, revealing to Sister Verna Sauventreen that the book did have value in response to her destroying a boy's copy of the book because it had no intellectual or any other kind of value.
The teachings of faith exemplified in the book when the three heroes, Bonnie, Jessup, and Geraldine, escorted a group of injured people across a poison river is later used by Richard Rahl and Sister Verna Sauventreen in their journey through the Valley of the Lost. Richard and Verna place their faith in their horses, similar to the faith the injured people placed in their congruently named heroes, to lead them out of the valley when Verna is unable to sense the way, saving them from being trapped forever in illusions created from their own memories.