"You shall not covet" is probably one of the most misunderstood of the Ten Commandments. Coveting isn't simply desiring something. Nor is it simply admiring something that we don't have. To covet is to become devoured by desire for something. And many times, it's something that isn't yours to have.
The word for covet
is also translated "to pant after." Think of a wolf that has gotten a taste for blood and is out there pursuing his prey, panting after it. That wolf will not rest until he catches his prey, kills it, and eats it.
That is what coveting is. How does it work? You become obsessed with something. First the eyes look at the object, the mind admires it, and the will goes over to it. Lastly, the body moves in to possess it. One thing leads to another.
Judas Iscariot effectively threw his life away for thirty pieces of silver when he betrayed the Lord. We are told in 1 Timothy 6:10, "For the love of money is a root of all kinds of evil, for which some have strayed from the faith in their greediness, and pierced themselves through with many sorrows." That verse is often quoted as "Money is the root of all evil," but the Bible says no such thing. The love of money
is the root of all kinds evil. It doesn't mean that it's bad to want some money. But it becomes a problem when we covet, or pant after, it.
Some people covet throughout their lives. They become obsessed with certain things and will make any sacrifice to get what they want. It may be a person. It may be an object. It may be a position. Whatever it takes, they are determined to get it. And it can destroy them.