"Good is not good because the gods approve of it, but the gods approve of it because it is good"
"a human being's main goal is to become a better person through the pursuit of knowledge, which is arrived at through reflection and dialogue
"What makes man sin is lack of knowledge"
"were I to make any claim to be wiser than others, it would be because I do not think that I have any knowledge of the world when in fact I have none."
Socrates (Plato)
Thought I'd throw a little greek philosophy on the subject. The Greeks attempted to figure this out and in the end influenced a great many of the christian religions. A good deal of the catholic doctrine is based on Greek beliefs, especially those of Plato.