From publisher blurb:
Guardians of a sacred trust, the celestial knights are a chivalrous order dedicated to guarding against the schemes of undead and any plots to increase the power of necromancy and undeath. The order is deeply religious, composed of devoted worshipers.
Prestige Class: Celestial Knight
Base Classes: Cavalier, Ranger
Role: A celestial knight is the champion of his faith and a potent protector for his allies.