everyone in salem believes not to kill nor murder but their going against the ten commandments because their hanging people are are innocent.
The people of Salem reacted more to fear and superstition than anything else, and once fear took over it created an atmosphere of uncontrolled hysteria. Everyone in the community became involved in one aspect of the trials or another. Gradesaver's theme of Community vs Individual explains this in detail.
"Salem is a tight-knit community where there is no such thing as private business. Individual activities like church attendance or book reading or keeping poppets become admissible evidence in court. Miller speculates that the community of Salem sought to keep itself together by casting out undesirable individuals, and in so doing created the atmosphere necessary for the witch hunts. The court itself was an extension of this principle, desperately in search of external validity – Danforth cannot possibly exonerate some when others have already perished for the same crime. But for the accused, it is only the individual that matters. In the end, Proctor is left with nothing but his name and reputation."
The Ten Commandments were a part of the church and cited in the text. The Mosaic Law not used in the text would be "Thou shalt not suffer a witch to live." (Exodux 22:18/ KJV) This particular verse has been debated for years in its translation, and witches (or those accused of witchcraft) have been executed in a number of different ways throughout history.
http://www.gradesaver.com/the-crucible/study-guide/major-themes/
