Definition of Fasting vs. Abstinence
Fasting refers to how much food we eat and, historically, when we eat it. It means taking only one meal during a calendar day. The meal should be an average-sized meal as overeating at the one meal is against the spirit of the fast. Fasting generally means that the meal is to be taken later in the day. Along with the one meal, up to two snacks (technically called either a collation or frustulum) are permitted. These are optional, not required. Added up together, they may not equal the size of the one meal. No other snacking throughout the day is permitted.
Abstinence in this context refers to not eating meat. Meat refers to the fleshmeat of mammals or fowl. Beef, poultry, lamb, etc are all forbidden on days of abstinence. Abstinence does not currently prohibit animal byproducts like dairy (e.g. cheese, butter, milk) or eggs, but in times past they were prohibited. Fish is currently permitted along with shellfish and other cold-blooded animals like alligators. In times past, days of fast were always days of abstinence as well; however, not all days of abstinence were days of mandatory fasting.
The Church’s Law in 1917
The days of obligatory fasting as listed in the 1917 Code of Canon Law were the forty days of Lent (including Ash Wednesday, Good Friday, and Holy Saturday until noon); the Ember Days; and the Vigils of Pentecost, the Assumption of the Blessed Virgin Mary, All Saints, and Christmas. Partial abstinence, the eating of meat only at the principal meal, was obligatory on all weeks of Lent (Monday through Thursday). And of course, complete abstinence was required on all Fridays, including Fridays of Lent, except when a holy day of obligation fell on a Friday outside of Lent. Saturdays in Lent were likewise days of complete abstinence.
The Church’s Law in 1962
By 1962, the laws of fasting and abstinence were as follows as described in « Moral Theology » by Rev. Heribert Jone and adapted by Rev. Urban Adelman for the « laws and customs of the United States of America » copyright 1961: « Complete abstinence is to be observed on all Fridays of the year, Ash Wednesday, the Vigils of Immaculate Conception and Christmas. Partial abstinence is to be observed on Ember Wednesdays and Saturdays and on the Vigil of Pentecost. Days of fast are all the weekdays of Lent, Ember Days, and the Vigil of Pentecost. » If a vigil falls on a Sunday, the law of abstinence and fasting is dispensed that year and is not transferred to the preceding day. Father Jone adds additional guidance for the Vigil of the Nativity fast: « General custom allows one who is fasting to take a double portion of food at the collation on Christmas Eve (jejunium gaudiosum). »
History of St. Patrick’s Day in Lent
Back in Ireland, St. Patrick’s Day was a Holy Day of Obligation and still, without special dispensation, a day of mandatory fasting and abstinence. Interestingly, « The Catholic’s Pocket Prayer-Book, » published by Henri Proost & Co. in 1924, notes that for Australia and New Zealand, all days in Lent were days of fasting « except Sundays and St. Patrick’s Day. » The same pocket guide lists the days of fasting and abstinence for Ireland and lists no such exception. Yet even for Australia and New Zealand, no exception for abstinence existed on St. Patrick’s Day in 1924.
Conclusion