Venerable Fulton Sheen
“Contentment, therefore, comes in part from faith – that is, from knowing the purpose of life and being assured that whatever the trials are, they come from the hand of a loving Father. Secondly, in order to have contentment one must also have a good conscious. If the inner self is unhappy because of moral failures and unatoned guilt, then nothing external can give rest to the spirit. A third and final need is mortification of desires, the limitation of delights. What we over-love, we often over-grieve. Contentment enhances our enjoyment and diminishes our misery. All evils become lighter if we endure them patiently, but the greatest benefits can be poisoned by discontent. The miseries of life are sufficiently deep and extensive, without our adding to them unnecessarily.”
Source: Ven. Fulton J. Sheen, Way to Happiness, St. Pauls, 1998.