Have you ever gone to a masquerade party? Everyone goes as someone he or she is not. The masquerader assumes a different identity and takes great pleasure in confusing people. With his identity masked, the masquerader is emboldened to do things he would never attempt if his true identity were discerned.
The chief masquerader of all time is the false, lying conception variously named in the Bible Satan, Lucifer, devil, serpent, dragon, carnal mind, liar, evil spirit. Isaiah quotes Lucifer as saying: "I will ascend above the heights of the clouds; I will be like the most High." Isa. 14:14. What a presumptuous masquerader—evil masquerading as good! And we're often taken in by this phase of evil. In fact, there's even a name for people who present an innocent front, while behind the "mask" they're quietly preparing to attack: wolves in sheep's clothing. Such was Judas Iscariot, Christ Jesus' unfaithful disciple. Judas sat with his Master at their last supper, his benign appearance masking a deceitful plot. But Jesus' pure spiritual consciousness was undeceived by evil. He was able to see through the mask and foretell exactly what Judas was going to do.
Mary Baker Eddy, who discovered and founded Christian Science, referred to this lying presumption—the discordant action of mortal mind—in such terms as animal magnetism, mesmerism, hypnotism, occultism, necromancy, and malpractice. She removed its mask and mystery as she further defined it as "aggressive mental suggestion." Manual of The Mother Church, p. 42. The evil is aggressive because it pushes, assaults, and attacks. It's mental because the aggression takes place within thought. And it's suggestion because it's something that's put into thought.