What does Mary Warren mean when she says, "I saved her life today!" in Act Two?
When Mary returns to the Proctor home after her day in the Salem court, John angrily threatens to whip her. He is angry because she has defied his order to stay away from Salem. Moreover, he is shocked and irate that his teenage servant is involved in the deadly accusations that have already condemned 39 villagers.
John becomes enraged when Mary tells him "the Devil's loose in Salem," and he raises the whip, announcing "I'll whip the Devil out of you!" Mary stops him with five words: "I saved her life today!"
Elizabeth is stunned to hear that her name has come up in court, but Mary assures them both:
"But I said I never see no sign you ever sent your spirit out to hurt no one, and seeing I do live so closely with you, they dismissed it."
Unfortunately, Mary overestimates her authority with the court and underestimates the deviousness of Abigail Williams. Though Mary will not divulge the information that it is Abigail who made the accusation, the Proctors understand who is behind the accusation.
Mary acts as a character witness before the court. She tells them she has not seen the witchcraft Elizabeth has been accused of. Her words literally did save her life, for a time.
Mary informs Elizabeth and John that she told the council "...I said I never see no sign you ever sent your spirit out to hurt no one, and seeing I do live so closely with you, they dismissed it."