Shorty Monster has a post over on his blog about religion in role playing games. His complaints are essentially three points: all fantasy games have the “same” gods, where “same” means that they follow similar “sphere of influence” styles; devotees of fantasy religions don’t behave the way devotees of real-world religions do, in that they are all “a homogenous lump” of identical personalities; and that fantasy religions are more-monolithic and less-fractured than real-world religions.
I think the the first point may be a valid observation, but I think it’s because each fantasy setting is trying to work off the same trope, ie, the Greek or Norse pantheons. I don’t think that’s really a problem, the same way I don’t think ripping inspiration from other sources is a problem. If it unnecessarily limits your choices then it’s a bad thing, but that’s true for any source of inspiration and can easily be fixed (by adding a new god, a new religion, or changing the way current gods and religions behave).
The other two points are really more about how devotees and religious organizations are played, rather than a problem with their foundation. Shorty notes that not a lot of details are given about dogma or observances (though, looking up Greyhawk gods on Wikipedia gives you quite a bit of information) and complains that there isn’t enough to go on to portray a devout character. That may be a fair point, but 1) I think a lot of it is left for the GM to fill out, because GMs tend to want to customize and build the setting to their own tastes (your mileage may vary as to whether that’s a sufficient excuse for leaving out material), and 2) I don’t think most fantasy gods or religions are based on strictly-ordered religions like modern real-world religions. A character prays to Pelor because he wants a strong crop yield, not because Pelor imposes a certain moral paradigm. A cleric devotes himself to Kord in order to embody strength and victory, not because Kord is the one true god. And a cult leaves offerings for Nerull because they fear him, or wish to direct him towards their enemies, not because of… well, OK, I’m at a loss for what else might motivate them.
For my part there are two things that I’m concerned about in my fantasy religions: the problem of divine accessibility, and the problem of definitive orthodoxy. They’re really both related to each other, but it’s the difference in how you approach the issue.
Why do Good Gods let Bad Things happen?
Putting other things aside, a common theme in fantasy setting (whether it’s RPGs or books or movies) is that the heroes have to go out and fight evil because they’re the only ones who can. But if the gods actually exist, especially if they have great powers to act upon the world, then why don’t they just fix the problem? If Pelor hates the undead so much, why doesn’t he just wipe them out with a miracle, instead of sending frail mortals to hunt them down and destroy them one-by-one? If Moradin protects the dwarves, why doesn’t he smite the hobgoblin army that’s laying siege?
This can be handled in a number of ways. Perhaps the god’s attention is elsewhere, addressing a greater threat like an Evil god working at cross purposes, and an unseen enemy who would overtake our heroes if not for the god’s interference. Or maybe the god is hesitant to interact with the world directly because doing so would make him vulnerable to his enemies (sapping his energy, or forcing him into an assailable state), and so directing mortal agents is the safer (if less sure) method of influencing the world. Perhaps Pelor can’t root out the undead because he has no power in dark places (though, if that’s the case, questions about the nature of clerics and divine magic come up), or perhaps in directing his power against the undead there would be innocents caught up in the destruction. Superman doesn’t have to be the only one who lives in a world of cardboard.
How can we argue about the will of Zeus if we can just ask him directly?
Here’s the problem: if we can speak to the gods directly, and they can answer us directly, it is essentially impossible to have a difference of opinion on what that god wants us to do. Two reasonable people can’t argue over whether killing cows offends Zeus or not if they can just ask him directly and get a clear yes or no. And because of this, you can’t have different sects that worship the same god coming into conflict or working at cross purposes. Any question or conflict internal to the church can be resolved by asking The Big Guy what takes priority. The Abrahamic/Judeo-Christians among us might point to the earliest days of their faith and note that just being able to talk to your god doesn’t prevent misunderstandings, but given time and opportunity those things can be cleared up: someone’s right and someone’s wrong, and it’s just a matter of asking the question.
This one is harder to fix, I think. On the one hand, you could allow your gods to make inconsistent or conflicting statements, and you could even hand wave it by saying that he knows more than mortals and just has a hard time expressing all the nuance that occupies a god’s mind. It strikes me that that would be a pretty difficult god to follow or put much faith in, because it essentially boils down to “we do not and can not know what he wants,” which is a sure path to agnosticism if nothing else. Followers of such a god will probably find other gods to cling to.
Alternatively, you could restrict talking to the gods to just their clergy, and so lay people could have arguments among themselves just fine. The trouble is that then “just ask Zeus” simple becomes “just ask Zeus’s priest,” and the best you can hope for is a wicked priest intentionally acting against his professed god. And when 9 out of 10 clerics agree, the 10th one must be a filthy liar. I really think that for fantasy religions to “work” in the sense of reasonable and committed devotees disagreeing with each other (especially to the point of conflict) the gods must be remote enough or vague enough that getting clear and simple answers is not clear or simple.
Good, Bad, I’m the one with the Holy Symbol
My preference is to have remote and disinterested (or preoccupied) gods. Maybe they live on Mount Olympus and even getting an audience with them is an epic quest. Maybe they exist outside creation and can not directly interact with it for fear of annihilating it (or themselves). Maybe they don’t even actually exist, and at best the gods are magical creatures like Elementals or Dragons and clerics are essentially sorcerers and witches. It doesn’t really matter (unless I’m directly addressing the question with my campaign) because the gods don’t really matter to me. They aren’t what I’m interested in.
The things that interest me in role-playing games are the characters (PCs and NPCs) and the societies and organizations they interact with. In most cases what a character or group believes is is far more important (and interesting) than what is true. So I tend to have the nature of the gods be an open question, because it’s not high on my list of priorities, and leaving it unanswered allows for a lot more variation in the religions and interactions available in my world.
Jack's Toolbox 
Very good points sir, and I’m glad my blog has gotten people thinking and coming up with a whole raft of ideas and answers.
Knowing the will of Zeus in general, not so difficult, knowing exactly what he wants is more of a challenge. It is not as if every employee of a multinational knows (or cares) what the CEO wants done and how, but they know the general goals of the organization. So, you should be able to have considerable low level conflict and disputes within a faith even if the big man can be asked for directions and clarifications now and then.
That’s kind of the point I was making, though; you might have small differences at a low level, but eventually someone in authority is going to say “knock it off,” and unlike in the real world “in authority” means they actually spoke to Zeus, and that’s not something you can argue with and still claim to be following Zeus. It’s less and less of a problem the further up you push it and the more rare/difficult the communication, until no one can talk to Zeus and it’s not a problem (and you can have all sorts of differing groups claiming to follow him).
I am going to answer some of this on shortymonster’s blog as well, but while I agree with most of what you say in this article, I would say that there are still ways, despite the ostensible willingness of Zeus to provide clarification to top priests, to get large-scale division in an organized religion around an accessible being, most of them revolving around the frailties of people. What Zeus chooses to care about and what a person or priest chooses to care about only need to intersect to mutual benefit, avoiding whatever it is which might upset Zeus. Power struggles over details like wearing white or not eating salted fish are the province of the power-hungry, and/or unreasonably devout.
A nice element as well is in the concept of the source of a deity’s power. If the deity is not just empowered, but given shape by the beliefs and faith of its worshippers. The tides in culture and society can bring about a variety of aspects for a deity, each seeking prominence.
To your first point, you may be right but is still feels off. Unless there’s only one priest who can talk to Zeus all it takes is someone else asking it eating fish is OK; once Zeus says he doesn’t care, you either step in line or you’re “wrong.” As I said before, making a god less accessible makes these problems less pronounced, but that’s kind of my point — and the basis of my preference for having gods essentially inaccessible.
To your second point, I really like that idea, and I’ve seen it floating around in literature and game settings. It solves a lot of different problems, including why a god might stay mute on certain issues (choosing to let the people decide if eating fish is OK or not, and either taking worship from both groups or siding with whoever gets the majority).
Well, we are starting to get into very specific what-if chains and detail-heavy territory now. What I want to add is just that Zeus’s answers about fish, bulls, capitalism or whathaveyou should be open to interpretation, and the deity should not be confused with the people who worship it. They should exist on a greater plane of being, and much of what either side really thinks and feels should be missed by the other. The key point for enduring is that this disconnect is not recognized, and the tendency of people to persist in traditions, rooting for the same team, or tossing salt over a shoulder plays a huge role in the development and persistence of a religion.
As for the second point, I think it is very cool, too.
Most of these problems are solved by making gods:
1. Not omnipotent (most gods were not omnipotent until the advent of monotheism in the real world)
-or-
2. Powerful creatures that actually reside somewhere, like a volcano (as opposed to being abstract, or even off in another plane like D&D often assumes). See also:
http://dreamsinthelichhouse.blogspot.com/2011/12/mythic-geography-and-d-setting.html
In both cases, talking to the god is probably not possible. At best, you might be able to summon an emissary. I know early D&D states (I forget where) that spells above a certain level involve talking to the god directly, but I don’t particularly like that myself (your post above is a pretty good explication of why).
The BECMI take on immortals (vaguely reminiscent of Buddhist bodhisattvas) is also a nice approach.
No matter what is chosen, there is no need to share the absolute metaphysics with players. Just let them adventure and figure it out! All they need to know is that they have these holy scriptures (or sutras, or interpretive dances) and a tradition, and when they do these things, they get powers. Maybe all gods are actually imprisoned sorcerer kings, trapped underground. Or orbiting AI satellites, like in Anomalous Subsurface Environment.