From publisher blurb:
The core rules offer two classes that specialize in organized religion: paladins and clerics. But why do all holy men have to be soldiers, clad in armor and wielding weapons? Most religious leaders from history were clad in robes, and drew power from their faith.
The priest is a 20-level core class for those heroes who are truly devout followers of their faith and do not spend any of their time learning military weapons or tactics. Like wizards and sorcerers, priests do not wear armor or use military weapons. Instead, they are armed with spells, followers, and bard-like abilities to influence people with their speeches. They are powerful healers and formidable enemies of undead and demons. Priests often outrank paladins and clerics in the church hierarchy and usually rise to the highest levels of authority.