The Reverend Parris is indeed a troubled minister. He is paranoid and has, from the outset, made claims of a faction who wishes to turn the townspeople against him. He has consistently sworn that there are those in the village who want to oust him. The leaders of this faction are supposedly John Proctor and Rebecca Nurse. The Reverend fears these two since both are very strong and much admired individuals in Salem.
Rebecca is admired and respected for her moral strength, her common-sense values, her goodness and her intellect. John Proctor is admired for his outspoken views, his openness and the fact that he is not afraid of anyone and is bluntly direct. He has repeatedly criticised the Reverend's desire to enrich himself at the congregation's cost, by for example seeking gold candlesticks for the pulpit and wanting to get the title deeds to the rectory.
Reverend Parris sees these two as his main enemies and he is afraid that their execution would cause a riot in the village. He has already claimed that there have been threats against his person. He fears that he would be driven out of town should Rebecca and John be hanged without the two of them providing written confessions.
It is especially John's written confession that Reverend Parris seeks. The confession must then be displayed publicly. Parris believes that since John is so much respected, a confession to witchcraft by him would ensure peace in Salem and of course, his security.
Since it was his daughter and his niece who had been discovered dancing in the woods and who had started the accusations of witchcraft, the Reverend has come to believe that his congregation thinks of him incapable to provide them spiritual guidance and protection against evil, since he could not even do it in his own home. Confessions by John and Rebecca would absolve him from blame, since they would make it clear that they are responsible for the evil which has infested their village.
The hangings have, therefore, to be postponed until written confessions by both accused have been obtained and these have been publicly displayed.