From publisher blurb:
This book contains the sacerdote base class, a new base class for the Pathfinder roleplaying game.
The sacerdote is a wisdom and intelligence class, a scholar and divine spellcaster class that is powerful and versatile enough to compete with the arcane wizard. Specialized in magic, they are less practical than clerics and are not leaders or warriors. They cast cleric and domain spells, know numerous divine secrets, and can use all the domains of a typical deity or draw power from a whole pantheon. They have a huge number of spells per day and rely on magic in combat and on channeling their spells into devastating manifestations of divine wrath.
This book contains rules for the sacerdote, including 23 feats and eight archetypes, the augur, invoker, proselytizer, theurgist and the druid, elemental, healing, and spirit sacerdotes.