Many people believe that life should be arranged by self center desires. That is a common mistake.
The world system will make you very sad. You need to oppose this system.
Contentment begins with righteousness. It is a big word but I will tell you the meaning of this word.
The word means to be correct. Mankind is sinful but God is not. If a person repents from their sins and follow Jesus, then then that person will be made clean. God sees that person as they never sinned.
The follower of Jesus will have new desires. When a person follow Jesus then the person is complete.
The Christian can work with great joy.
Many people will reject Jesus. The sinful nature will reign in the sinner's life. They are never content.
They will complain about life. The wicked person can have many things but they are never happy.
Jesus gives purpose in this life.