What relationship did the stranger have with the others in the village?

Reader interpretation might vary a little bit on which word best describes the relationship that exists between the stranger and the people of the town. The stranger is actually the devil, and as Young Goodman Brown discovers, the devil and the people of the town know each other quite well. Everyone that Brown believed to be good and pious is actually in league with the devil. A reader might be able to make a claim that the people and the devil are friends, but I do not think that this is the best descriptor of the relationship. I would say that the relationship is more akin to that of a master and servant. The devil has gotten good people to join his side, and he leads them to do his evil work. A good example is Goody Cloyse. Goodman overhears a conversation between Cloyse and the stranger, and Goodman learns that Cloyse is a witch and a devil worshiper.

"Then Goody Cloyse knows her old friend?” observed the traveler, confronting her, and leaning on his writhing stick.

The devil calls her "friend," but she does not refer back to him that way. She refers to the devil as "your worship." That wording leads me to believe that the relationship is not a friendly relationship between equals.