Fasting and Abstinence1. Nowadays fast and abstinence take the form of precepts of the Church which bind us under pain of mortal sin. Before they were commanded by the Church, however, they had been commanded by God. God made the first law of this kind when He ordered Adam to abstain from the forbidden fruit. Moses made particular laws of fast and abstinence for the Jewish people. He also fasted himself, as did the prophet Elias. “My knees totter from my fasting,” writes King David, “and my flesh is wasted of its substance.” (Psalm 108:24) “Prayer is good with fasting and alms,” (Tob. 12:8) says Tobias. Jesus fasted for forty days as an example to us and He warned us that the devil can be conquered only by prayer and fasting. (Mt. 17:20) In a more general way, He warned us that: “Unless you repent, you will all perish.” (Luke 13:5) One of the means of doing penance most often recommended in Sacred Scripture is fasting and abstaining.
Why, you may ask, should Our Lord and the Church command us to mortify ourselves in regard to food? There is a strong reason. It is an act of obedience to God, our absolute master, Who does not demand anything of us save for our own welfare. Secondly, it is an act of reparation for our sins. In the third place, it enables us to subdue our carnal impulses and in this way makes us more obedient to the law of God. A man who cannot mortify his appetite for food will certainly not be able to resist the temptations of the flesh. There is a connection between all these things. If we cannot subordinate our bodily appetites to our spiritual faculties and to the divine law, we shall not be able to raise ourselves from the level of an animal existence to contact with God through prayer and the practice of virtue.
2. It is irrelevant to object that there is no harm in eating one kind of food rather than another. In fact, this is not a question of food at all. It is a question of obedience to the laws of God and of the Church. God is the supreme Lord of heaven and earth and it is wrong to disobey His commands. Similarly, it is not permissible to disobey the precepts of the Church which Jesus Christ founded to be our infallible guide. God commanded the Hebrews to abstain from blood-meat and from so-called unclean animals. Today the Church has set aside a minimum number of days of fast and abstinence. How can we ignore the commands of God and of the Church? To do so would be an act of rebellion against the highest of all authorities as well as a sign of indifference to our eternal salvation. Even the purest of the Saints, such as St. Aloysius Gonzaga, constantly mortified themselves in this way. "If you have sinned, do penance," writes St. Augustine. If we reflect on the number of our sins, the insignificant degree of fast and abstinence demanded by the Church today will not seem excessive. Indeed, we should be glad to fast and abstain a little more than is necessary in order to expiate our sins and to gain control over our carnal instincts. Let us show God how much we love Him by being prepared to undertake voluntary mortification.
3. Other objections are sometimes raised against fasting and abstaining. These include poor health, excessive work, a frail constitution, and so on. Such reasons for exempting ourselves should be carefully considered before God and in consultation with our confessor. If they are genuine, we are entitled to omit fast and abstinence either partly or entirely. God is more interested in our good intentions than in any material act, which is demanded only as a proof of our good will.
If we cannot actually fast and abstain we can mortify ourselves spiritually. We can curb our tongues by avoiding idle and uncharitable conversations. We can mortify our eyes by avoiding looking at anything which might lead us into danger. We can mortify our hearing by seeking a certain degree of solitude and silence. We can mortify our bodies by depriving ourselves of unnecessary luxuries. Above all, we must abstain from sin and from the occasions of sin. This is the basic fast which we are all obliged to keep at all costs by means of constant and fervent prayer.