Most of the time it is the circumstances that determine our attitude. If life is going as we wish, we feel content and good. But when the situation turns for the worse, our mood turns into gloom. A believer need not live like this.
Many people are not really content in what they have. They may be blessed with all what they need in life. Still they are not content. They may not have contentment with respect to their family life, their spouses, their children, their jobs, etc.