The peasant claims that his village is suffering from a terrible curse, and that it needs brave and sturdy adventurers such as themselves to help.
If the players show continued interest, the peasant will tell them of a daemon in human form who has assumed the form of the village priest. He proceeds to beg the adventurers to get rid of the daemon before he can perform even more rituals in the name of his dark god.
He then tells them were they can find the church and also explains what the priest looks like.
Possible reasons for the encounter
1-A priest possessed
A daemon really has taken over the priest and is seeking to call down ruin and destruction upon the village and its inhabitants.
The real priest is of course long dead, the daemon having consumed his soul thus gaining his form and free to cause destruction as he pleases.
2-It’s truly amazing what a little disguise can do for you.
The peasant is in fact the daemon who has taken his form, and is taking a different tack. Instead of wasting all of his time and energy by taking control of someone really high-standing in the village community, the daemon has decided to use the peasants form to get any passing adventurers to seed chaos and confusion into the hearts of the villagers so as to spread as much mayhem as is possible.
Using the adventurers to unwittingly do his dirty work for him is just his sort of thing.
In reality there is no daemon just a very angry community with an exceedingly greedy priest who imposes loads of fines upon things which other priests would consider petty and a waste of time, finding ways to empty the villagers pockets as quickly as possible.
Finally someone has gotten angry enough to get him killed so he is going round to adventurers spreading the word that their priest is a daemon in human form in order to have him killed for the injustices he has done the people.
He figures that if this is the end awaiting the current priest, that the next one will be more lenient.
Or what if…
However if your group of adventurers are slightly more intelligent than the rest out there and decide to do a little bit more digging around in the village to determine what the peasant says is true or not.
It would provide them with several opportunities.