In Luke 6:45 (NLT), God tells us, "A good person produces good deeds from a good heart, and an evil person produces evil deeds from an evil heart. Whatever is in your heart determines what you say." This tells us that our actions and words reveal who we really are. And that we best relate to others by being open and honest.
As a writer, I know people can tell if I'm being honest by the words I use. They know if my statements are coming from my heart or from a world view that says, "Tell them what they want to hear, then you'll gain wealth and popularity." However, doing anything just for the sake or earthly rewards will never provide true joy and peace. The only sure way to happiness is to follow the heart God gives us, without regard for material rewards.
It's true that some evil people will experience worldly success. But they will not truly be happy because they have to spend their lives worrying about how to keep what they have from others. And, in the end, they will be placed in a box, dropped into a hole and covered with dirt. All their stuff will be left behind to be divided up by the very people whom they spent their lives trying to keep it from. So what have they really accomplished?