Saint John Chrysostom (c. 349–407)
For let not the mouth only fast, but also the eye, and ear, and the feet, and the hands, and all the members of our bodies. Let the hands fast, by being pure from rapine and avarice. Let the feet fast, but ceasing from running to the unlawful spectacles. Let the eyes fast, being taught never to fix themselves rudely upon handsome countenances, or to busy themselves with strange beauties. For looking is the food of the eyes, but if this be such as is unlawful or forbidden, it mars the fast; and upsets the whole safety of the soul; but if it be lawful and safe, it adorns fasting. For it would be among things the most absurd to abstain from lawful food because of the fast, but with the eyes to touch even what is forbidden. Dost thou not eat flesh? Feed not upon lasciviousness by means of the eyes. Let the ear fast also. The fasting of the ear consists in refusing to receive evil speakings and calumnies. “Thou shalt not receive a false report,” it says. (St. Chrysostom: On the Priesthood; Ascetic Treatises; Select Homilies and Letters; Homilies on the Statutes: Hom. III)
I have said these things, not that we may disparage fasting, but that we may honour fasting; for the honour of fasting consists not in abstinence from food, but in withdrawing from sinful practices; since he who limits his fasting only to an abstinence from meats, is one who especially disparages it. Dost thou fast? Give me proof of it by thy works!
Sharpen thy sickle, which thou hast blunted through gluttony—sharpen it by fasting. Lay hold of the pathway which leads towards heaven; rugged and narrow as it is, lay hold of it, and journey on. And how mayest thou be able to do these things? By subduing thy body, and bringing it into subjection. For when the way grows narrow, the corpulence that comes of gluttony is a great hindrance. Keep down the waves of inordinate desires. Repel the tempest of evil thoughts. Preserve the bark; display much skill, and thou hast become a pilot. But we shall have the fast for a groundwork and instructor in all these things. (On the Priesthood)
Do you fast? Prove it by doing good works. If you see someone in need, take pity on them. If you see a friend being honored, don’t get jealous of him. For a true fast, you cannot fast only with your mouth. You must fast with your eye, your ear, your feet, your hands, and all parts of your body. (On Fasting)
As bodily food fattens the body, so fasting strengthens the soul. Imparting it an easy flight, it makes it able to ascend on high, to contemplate lofty things, and to put the heavenly higher than the pleasant and pleasurable things of life.
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