What is the importance of The Book of Counted Shadows in the novel, Wizard’s First Rule?

The Book of Counted Shadows is a sacred text that describes how to open the three boxes of Orden, and most importantly, which box to open. The great wizard Zedd hid it at Aydindril, guarded by a huge beast who was the keeper of the book. Richard's father, George Cypher, killed the beast and stole the book to keep it away from Darken Rahl's father. This made George Cypher the keeper of the book. To protect the book even more, George had his adopted son Richard memorize the book, line by line, over a number of years. When Richard could recite the book perfectly, they burned it. This makes Richard the keeper of the book, even though what he keeps is the knowledge, not the physical book itself.