So he's trying to pay a god with silver or gold to do him a favor? What good is money to a god?
As Graham has said, the point of the sacrifice is not that the god benefits from the gift but that you surrendered something willingly.
It's exactly like people who pray and make promises to go to church or stop doing something they think God doesn't want them to do or to start doing something they think He does want them to do. I don't think much of those bargaining prayers, but they illustrate the principle of sacrifice: from the petitioner's perspective, he is offering something to God (or a god) to appease and appeal for something in return.
There's a story told about a guy who was going to be late for an appointment if he didn't find a parking space fast. The entire block was filled, and he'd been around it twice. Finally he says, "God, I'm really in trouble here; I've got to be on time for this appointment. If you'll get me a parking space, I'll be sure to give you half of my next paycheck and attend church ever weekend next month." Suddenly a car pulls away from the curve right in front of him, exactly in front of the door of the building he's trying to get to. So he says, "Never mind, Lord, I just found one myself."
And to some degree we're trying to avoid that; but we're also trying to avoid giving someone credit for a price they never paid.
It seems like the precise god may be the deciding factor between whether payment has to occur or not.
That can't be the direct answer, though; that is, it can't be that a different rule applies to one religion than to another as far as the value of promised sacrifices.
However, I can see that it can be an indirect answer. That is, the expectations of the user are paramount here. If the user believes that having made the promise he must fulfill his bargain even if his prayer is not answered, then his sacrifice is worth more than that of a person who believes that his obligation to make the sacrifice is contingent upon the prayer having been answered. (That opens the complication of whether the character necessarily knows that his prayer has been answered, as our parking space example illustrates, but that's a problem for the god to inflict on the character.)
That aspect of expectations plays a deep role in all this. After all, I don't happen to think that The God is at all impressed by our promises to be good or go to church or give more money as a bargaining chip (He is impressed by them as expressions of gratitude, which is an entirely different aspect, as Scott observes). However, if a player character believes that he can bargain with God in this manner, his belief that he is offering God something of value (making a sacrifice) counts, whether it fits my Christian theology or not.
What happens if the verser makes a promise to sacrifice something they can access, then verse out and end up not bringing it along or being able to find a replacement?
My immediate inclination is that the character is a fool.
However, I can imagine it happening. I would suggest that such a character find a priest or other leader of his faith to whom he can explain the problem, and hope that the priest can discover from the god what solutions are viable. It may be that if I promised to give a certain magic item I own to my god and it is destroyed in my final battle or I verse out and arrive without it, the god might regard that as a sacrifice perhaps grudgingly made. It might be that an alternative form of atonement can be made by giving something the god considers to be of equal value plus interest. On the other hand, if I promised to sacrifice something that was not mine, with the intention that I was going to make it mine (get me through this, and I'll steal the crown jewels and deliver them to the temple at Memphis) that raises a lot of flags already, and I'm not sure I would feel sorry for a player whose character made that kind of bargain and "died" before he could fulfill it.
I have a question; when you have ritual components of a spell, are the components consumed if the spell fails?
Ah, there's a tricky one.
In a lot of cases, the "destruction" of the material components is integral to the casting of the spell in a mechanical way--I'm going to smash this gemstone with a hammer, pour the wine onto the dirt, burn the flesh on the altar, use the leaves and berries to make the ink with which I write the letters, drink the concoction, et cetera. What happens is that we "gloss" this in a lot of instances--Harry will use ten emeralds which will be "destroyed in the casting" by some means not mentioned such that he can never use them in any way again. I usually assume that they turn to dust or evaporate or some such thing--and I usually assume that they do so whether or not the petition is answered, because "destroyed in the casting" means that they are destroyed whether or not the spell succeeds. I waffle on this slightly, though--if you attempt to cast a spell in which the components are "destroyed" in some way that is not specified, and the spell itself is biased out, I probably won't destroy the components because no magic of that sort can work at all. That's a bit unfair, a bit unbalancing, and I might not be consistent with it; but on the other hand, if a possible spell fails and you used components that you were counting on destroying, I won't let you get away with using one spell to effect another--for example, if your intention> is to destroy a particular gemstone that belongs to the local ruler, and you get your hands on the gemstone and decide that the easy way to destroy it is to use it as the material component in your remove fatigue spell, if the spell fails I won't destroy the gem (because I can see through that ruse), although if the spell succeeds I will. (If you've gotten possession of the gem, you can use it for the spell, if you are actually casting the spell.) This prevents you from creating a spell with very little chance of success simply to use it to destroy valuable objects.
I've also sometimes asked players how they intend for their material components to be destroyed, but generally however it is, the components are destroyed even if the spell fails, although I will make an exception based on relative failure--for example, the other day John's summoning spell failed because he was interrupted, but it was never rolled (it was a GE roll that had to be good for him to have time to cast). If material components had been involved in that and he did not have to destroy them himself, I probably would have left them intact. Similarly, if the roll is bad enough that the magic didn't even begin to approach the possibility of working, I might leave the components.
So it's not a consistent rule, but generally yes, components destroyed in the casting are destroyed in the failure.
Thanks for the input; I owe Harry an answer, but I think I've got one now.
--M. J. Young