The value of fasting consists not in abstinence only from food, but in a renouncing of sinful practices. Do you fast? Give me proof of it by your works. If you see a poor man, take pity on him! If you see a friend being honored, do not envy him. Do not let only your mouth fast, but also the eye and the ear and the feet and the hands and all members of your bodies. Let the hands fast, by being free from greed. Let the feet fast, by ceasing to run after sin. Let the eyes fast, by observing modesty and disciplining them not to glare at that which is sinful. For it would be an instance of the highest ridiculousness to abstain from meats and unlawful food because of the fast, but with the eyes to feed on what is forbidden. Let the ear fast, by not listening to evil talk and gossip. Let the mouth fast from foul words and unjust criticism. For what good is it if we abstain from birds and fish, and yet bite and devour our brothers?
St. John Chrysostom