Quotes about fasting from throughout Christian History.
"The fasting," [the Angel of Repentance] continued, "is very good, provided the commandments of the Lord be observed. Thus, then, shall you observe the fasting which you intend to keep. First of all, be on your guard against every evil word, every evil desire, and purify your heart from all the vanities of this world. If you guard against these things, your fasting will be perfect.
"You will also do as follows: Having fulfilled what is written, in the day on which you fast, you will taste nothing but bread and water. Then, having reckoned up the price of the dishes of that day which you intended to have eaten, you will give it to a widow, orphan, or some person in want, and thus you will exhibit humility of mind, so that he who has received benefit from your humility may fill his own soul and pray for you to the Lord. If you observe fasting as I have commanded you, your sacrifice will be acceptable to God, and this fasting will be written down, and the service thus performed is noble, sacred, and acceptable to the Lord.
"These things, therefore, you shall observe with your children and all your household in this way, and you shall be blessed in observing them. And as many as hear these words and observe them shall be blessed, and whatever they ask of the Lord they shall receive." (Shepherd of Hermas. Similitude 5th. Ch. 3.)