There are several gods in the world. They are divided in many area of concerns and none is really more influent than another.
Here are the existing patheons:
Greater and Intermidate Powers
Lesser and Demi-Power Powers
Heros and Quasi Powers
Halfing and Gnome Power
Crunch information about Knowledge Religion
One must choose a patheon to which he will be familiar. This patheons becomes his knowledge reference and all checks within this patheon will be normal. For every other patheons a penalty will be applied depending on the type of information seeked and in which category the information falls into.
For example, someone choosing the Elven patheons will know much about elven gods, domains and influence, opposites gods. But will know much less about the human gods, so everytime he will want to know something about human divinty a penalty will be applied to his Knowledge roll.
Every 5 ranks into Knowledge religion enable the character to either select a new patheon or know even better his own.
This does not affect the ability to identify monsters such as undead.