The book says that they were dancing to the song from Barbados that Tituba was singing. Another reason they were doing that could be that Tituba was a witch or something like it and was doing some kind of sorcery or summoning. So it could be a lot of different things. Maybe she was doing some religious song and dance that Paris didn’t approve of it because he was a Puritan and wanted Tituba to get into trouble because of it. He wouldn’t let his reputation go down the drain. It could also be that she was a very religious person, and people that were of the same religion either followed her or thought she was high in their religion. So she could have wanted to teach or purify the kids for some reason. Betty could have been affected by some supernatural force or something. It could have looked like she was a witch to Paris. So there are a lot of reasons that you could come up with for it.

Casey