A Book of Shadows is a collection of spells and religious information and records kept by an individual or a coven. While sharing knowledge is encouraged, Wiccans should never share their Book of Shadows because they are very personal.
In the beginning of every Book of Shadows there is a Book Blessing, which usually rhymes. Here is mine:
Book Blessing
No evil shall enter
The pages held here;
For this book holds things sacred,
This holds memories dear.
May this book be blessed,
May this never be broken.
For with the All,
Only good words are spoken.