Reverend Parris says that line to Abigail Williams in act one of the play. He is trying to stress to Abigail that Betty's catatonic state could ruin him and get him removed from being the town's minister.
Parris is a self-serving minister. He's got a giant "holier than thou" type attitude, but men like John Proctor and Giles Corey see right through it. They see that Parris is a greedy man. They know that appearance matters more to Parris than substance. Parris knows this about himself too, which is why he is worried. Men like Proctor and Corey have not been shy about their distaste for Parris. Other people in the town likely feel the same way, which is why Parris mentions that there is a "faction sworn to drive me from my pulpit."
Parris is worried that the people of the town will think that Parris's own household has witchcraft in it. The people of the town will then use that as evidence that Parris is not truly a man of God and should be removed from the pulpit. I tend to agree with Proctor and Corey, because at that moment in the play, Parris is more worried about his own reputation than his daughter.