Why do Catholics fast?

Catholics fast because Jesus fasted and taught His disciples to fast. Christian fasting expresses repentance, trains the will, strengthens prayer, and makes room for generosity toward others.

What Jesus taught. Christ fasted for forty days in the wilderness before beginning His public ministry (Mt 4:1-2). He did not say, “If you fast,” but “When you fast,” and He warned against fasting merely to impress other people (Mt 6:16-18). He also said that His disciples would fast after the Bridegroom was taken from them (Mt 9:15). From its earliest centuries, the Church has practiced regular fasting as part of Christian discipleship.

What fasting accomplishes. Food is good, and fasting does not treat the body as evil. By freely giving up some food, Catholics learn that bodily desires should serve love rather than rule the person. Fasting supports conversion of heart and joins bodily discipline to prayer and almsgiving (CCC 1430, 1434). Money or food saved through fasting should, when possible, help someone in need. Fasting also reminds us that human beings do not live by bread alone, but by every word that comes from God (Mt 4:4).

What the Church requires. The Church’s minimum penitential discipline includes fasting and abstinence on appointed days (CCC 2043). In the Latin Church, Ash Wednesday and Good Friday are days of both fasting and abstinence from meat. The law of fasting binds Catholics from age eighteen until the beginning of their sixtieth year, while abstinence binds those who have completed their fourteenth year (Canons 1251-1252). A customary fast permits one full meal and two smaller meals that together do not equal another full meal. Those who are ill, pregnant, frail, or otherwise unable to fast are not bound when fasting would be harmful. They can choose another suitable penance.

How to fast well. Begin with prayer and a clear intention. Keep the fast quietly, avoid complaining, and resist turning it into a diet or personal achievement. Join it to a concrete act of charity. Voluntary fasting on other days can also be fruitful, provided it is prudent and does not damage health or neglect genuine duties. If you fail, do not abandon the effort. Ask God for grace, make a humble restart, and remember that the goal is deeper love of God and neighbor.