A theme in this story is that you can use cruelty to get what u want. Abigail is threatening to stab the other girls if they tell anyone anything about what happened in the woods that one night they were found. She uses cruelty to keep the girls quiet by telling them she will come to them at night while they're sleeping and kill them if they say anything about the night in the woods. This represents the theme because Abigail has threatened to kill the girls if they don't do as she says which is keep quiet.
In this scene Proctor is choking Mary Warren for not wanting to testify against Abigail. He is angry that she won't confess to the truth all for Abigail, so he chokes her and throws her to the ground and makes her eventually testify against Abigail. This represents the theme because Proctor has to abuse Mary Warren to get her to do what he wants.
In this scene Mary Warren just pretended to be under the devil's control again and accused Proctor of being the devil's man and accused him of witchcraft. This represents using cruelty to get what you want because Mary Warren just gave him the ultimatum of either confess and spend the rest of his life in jail or not admit to it and hang for it. She did that just to keep Abby safe and make her look good.