How did the Brownists/Calvinists justify capital punishment for witches?

My ancestors were Brownist pilgrims, leading up to the Salem witch trials, my Great-great-great-something-aunt was hung for having *a lack of the fear of God* in her. The people at the time were no doubt very superstitious, attributing misfortunes like infant death and crop failure to devils and the supernatural, and if someone was accused of being possessed by the devil, they were often arrested, or worse... The Mosaic law stated: > "Thou shalt not suffer a witch to live." (Exodus 22:18) But Paul taught in Romans 7 that the law of Moses was fulfilled in Christ. > "But now we are delivered from the law, that being dead wherein we > were held; that ***we should serve in newness of spirit, and not in the > oldness of the letter.***" (Romans 7:5;) Christ told his diciples to cast out devils: > "Heal the sick, cleanse the lepers, raise the dead, **cast out devils**: > freely ye have received, freely give." (Matt 10:8;) If the law was fulfilled and the new command was to cast out devils, then why was there a series of executions instead of exorcisms? In Salem Village, as in the colony at large, life was governed by the precepts of the Church, which was Calvinist. By what law did they justify capital punishment? Did the Calvinists hold to the old law even though it was fulfilled? Or did they have some other justification for executing people?