A book written by Skip Williams, Rich Redman, and James Wyatt detailing many of the powers of D&D 3rd edition. The book also formalizes what a power may or may not do.
The closest Planescape book is "On Hallowed Ground."
There was another book of the same title and basic theme in 1st edition D&D, which On Hallowed Ground used as a major source. Its second-edition equivalent was called Legends & Lore.
Deities and Demigods