Although there are different ways the word “envy” is used in modern parlance, often it is synonymous with “jealousy” and means the desire to have something like what someone else has. “I want a car like yours.” “I want a job like yours.” “I want a wife like yours.”

Such envy isn’t necessarily bad, if it motivates you to work hard to obtain something desirable that isn’t sinful. As long as you obtain the object of your desire legally and ethically, it can be rightfully yours.

Covetousness, however, is different. Covetousness says, “I want your car. I want your job. I want your wife.” This kind of longing goes beyond reasonable desire and leads to a person pining and mourning over something that they cannot obtain under righteous circumstances.

As a result, the only way to obtain what you covet is to commit sin: you commit adultery to obtain someone else’s wife, you commit theft to obtain someone else’s car, you bear false witness to obtain someone else’s job, etc.

That is why the Bible prohibits coveting in the Tenth Commandment. It leads nowhere good.