Envy (Latin invidia), like greed or lust, is characterized by insatiable desire. It can be described as sad or resentful greed for another person's traits or possessions. It arises out of vanity and separates a person from his neighbor.
Malicious envy is similar to jealousy in the sense that they are both dissatisfied with someone's traits, status, abilities or rewards. The difference is that envious people also want the object of envy and are eager to get it. Envy is directly related to the Ten Commandments, namely: "And do not covet ... what belongs to your neighbor." This statement may also be related to greed. Dante defined envy as "the desire to deprive other people of what belongs to them." In Dante's Purgatory, envious people are punished with wire-sewn eyes for taking sinful pleasure in seeing others humiliated. According to St. Thomas Aquinas, the struggle caused by envy consists of three stages: at the first stage, the envious person tries to lower the reputation of another; at the middle stage, the envious person receives either "joy from someone else's misfortune" (if he manages to defame another person), or "grief from someone else's well-being" (if he fails); the third the stage is hatred, because "sadness causes hatred."
Envy was the reason Cain killed his brother Abel, because Cain was jealous of Abel because God approved of Abel's sacrifice, not Cain's sacrifice.
Bertrand Russell said that envy is one of the most powerful causes of unhappiness, bringing grief to those who envy, and at the same time encouraging them to hurt others. According to the most common views, only pride weighs on the soul more than envy, among the main sins. Like pride, envy is directly related to the devil, since the Book of Wisdom of Solomon (Prem. 2:24) says: "the envy of the devil brought death into the world."