I think the most important point here, for both the cleric and non-cleric characters in these examples is also the simplest one: the characters you play aren't real you are always in charge of what they do.
I am a big fan of roleplaying and exploring interesting character ideas (believe me!) but at the same time, when you ultimately say "that's what my character would do!" in response to something that will cause a big problem for the campaign, it's a cop-out.
If you're playing a rogue who's going to steal from the group and randomly execute prisoners, then you can expect to get called on it at some point, especially if the group is good! When that happens, your actions may very well have been in character, but the rest of the group may not like them and may state that fact being equally in character. Maybe your gaming group is mature enough to handle this all in character, and if they are more power to you! If they aren't, however, playing the "it was just what my character would do!" card does not absolve you of what was happening. You choose the kind of stories you want to explore with each character you play, so that character who was always looking after no one but himself might be surprised when he gets his comeuppance, but you shouldn't be.
That goes the same way for the cleric side of things: you're choosing how devout your character is, as well as what they're going to be focusing on. If your cleric does nothing but buff himself in combat, expect both the other characters and the players to call you on it.
What solves a lot of these problems before they start is to have a character creation session where everyone sits down and talks about their characters. If you're going to play a warrior priest who doesn't believe in healing the weak, let people know about it. That way if the group is taking a "party based" approach to making characters, you can be classified as a warrior rather than a cleric. Similarly, that klepto rogue with a mean streak? Talk about that before the game starts! If the rest of the group has a cleric or paladin focus, better buck up on your use magic device skill and get yourself a wand or two!
There is a certain amount of suspension of disbelief that occurs in a game session about groups of characters that stick together in dangerous situations when they really shouldn't, but everyone has their own definition of how far this goes, so before a campaign starts, it's a good idea to get everyone on the same page.
And that's just my opinion, of course...I could be wrong...
--Steve
