If you have only one specific villager that needs to do the praying, and one temple, I think the following standard triggers would work:
Trigger: Active, Looping, Priority: High
Condition: Object in Area: villager near the temple
Condition: Object has Target: villager, temple
Condition: Timer: 1
Effect: Quest Var Modify: whatever quest var you want, by the amounts of points to get per second (like 0.1 for your example)
To display the message, you can use:
Trigger: Active, Looping
Condition: Timer: 30
Effect: Send Chat (or whatever): Player 1 has "+trQuestVarGet("QuestVarName")+" prayer points. (where QuestVarName is the name of the variable you use to store the prayer points. Put the quotes, brackets, etc as above to cause the value to be inserted right into the message.This would also work if you have a several villagers and several temples as long as they're all in the editor at the start.
Another way might be to use the player's favor amount. I think the Player Stat trigger includes the stat "Favor Total", which is how much favor the player gathered the whole game up to now. Gathering rates get slower as more villagers are assigned to a temple, but I think it should still be a pretty good measure. Experiment with how many prayer points should be gained per second by a villager to get the right rate.
If you let the player train as many villagers and temples as he wants, you could also use a custom trigger with a knowledge base query to find all the praying villagers and count them. I haven't done this in a while though, but if you really want I can try to write one up.
[This message has been edited by Matei (edited 12-31-2003 @ 07:30 PM).]