Answer:
Rev. Parris was so fearful that the villagers will discover his niece and daughter were amond the girls dancing in the woods because, in the village, it was part of the rituals of witches to dance around fire in the forest.
As a reverend who had already made enemies that wanted to see him fail and fall, this information would be a great instrument in their hands because he would be labelled a hypocrite, a reverend whose family practiced witchcraft and yet he preached against it.
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