Whatever is created has an emptiness to it. "Vanity of vanities! All is vanity" (Ecclesiastes 1:2) is what Solomon learned: creation of itself does us neither good nor harm; it is all like a wind. Nothing in creation is suitable for a godly person to feed on for good and happiness. The reason you are disappointed by the things of the world is not because you have nor accumulated enough of them. Rather it is because they are not in proportion to that immortal soul of yours that is capable of appreciating God himself. Many think they are unhappy because they do not have enough of the things of this world, but having more would not satisfy them. They are like a hungry man who tries to swallow the wind and who then thinks he is not satisfied because has not gotten enough of it! "Why do you spend money for what is not bread, and your wages for what does not satisfy?" (Isaiah 55:2). Are you crazy? Riches say "Contentment is not in me"; pleasure says "Contentment is not in me"; all created things say the same. Contentment is higher than that.
An excerpt from: The Rare Jewel of Christian Contentment edited and republished by Rob Summers, written by Jeremiah Burroughs, a British divine who wrote in the 17th Century during the British Civil War. Downloaded on my Kindle.