Cotton Mather, the author of this letters, in his time was a prominent minister in Boston, in the state of Massachusetts. The letters are testimonials of the witch trials who took place at Salem. Mather took active role during these trials although he wasn??™t a trial judge. The letters are describing some of the witch trials on who Mather attended. Mather??™s thoughts and his stick religious believes are revealed to us from his writing at The Wonders of the Invisible World. Yet he brings us, the reader closer, to the dark side of the society which was established at that time. Mather sees the sin as a transgression of the religious or moral laws. The theme in the story is about the people and their sinful nature. Mather sees the sin in the ???witches???, but from a distant, objectively, readers perspective we can see the sin that burdens the whole society. Society in which relatives, friends and neighbors accuse each other, of witchcraft, and the reason for such accusations are jealousy, greed or saving their own lives from the terrible trial. This unkind human behavior can be seen thru the example of Martha Carrier, a woman who is accused of witchcraft. It is sad that as accusers who claimed that Martha was a witch were her own children. The children even claim that Martha forced them to become witches too. Martha clearly stated that he is innocent of all chargers and during the remaining trial she decides not to speak on her own defense. The eyewitnesses, one by one, are pointing and accusing Martha for so many witch deeds, even to claim that she has a supernatural powers. Many of the observers in the end of the so called testimonials are convinced of every single word, and they all believe that what is said against her is true. Ironically even without even one fact, without true evidence they, the jury found Martha guilty of witchcraft. In the end she is executed and no one feels pity or remorse for her cruel fate. ???The wonders of the invisible world??? reveals the tendency of the crowd to blame a single person for their mistake and sins, in this case, everything un pure what was happening in Salem was Devil??™s deed, so they usually found worshipers of the Devil who needed to be purged for their sins. Mather sees himself as a God??™s tool, a tool who is needed to help the good to overcome the evil in the battlefield which was named Salem. Their sin, the sin of killing their loved ones, strangely was not seen as their own but as the sin committed from the Devil and his followers.