From the 1983 Code of Canon Law (CIC) 1249:
The divine law BINDS all the Christian faithful to do penance each in his or her own way. In order for all to be united among themselves by some common observance of penance, however, penitential days are prescribed on which the Christian faithful devote themselves in a special way to prayer, perform works of piety and charity, and deny themselves by fulfilling their own obligations more faithfully and especially by observing fast and abstinence, according to the norm of the following canons:
1. Can. 1250: The penitential days and times in the universal Church are every Friday of the whole year and the season of Lent.
2. Can. 1251 Abstinence from meat, or from some other food as determined by the Episcopal Conference, is to be observed on all Fridays, unless a solemnity should fall on a Friday. Abstinence and fasting are to be observed on Ash Wednesday and Good Friday.
3. Can. 1252: The law of abstinence binds those who have completed their fourteenth year. The law of fasting binds those who have attained their majority, until the beginning of their sixtieth year. Pastors of souls and parents are to ensure that even those who by reason of their age are not bound by the law of fasting and abstinence, are taught the true meaning of penance.
4. Can. 1253: The conference of bishops can determine more precisely the observance of fast and abstinence as well as substitute other forms of penance, especially works of charity and exercises of piety, in whole or in part, for abstinence and fast.
It is thus a matter of divine law that the faithful are to do penance (a fact we could have determined from Scripture), and the regulations regarding fast and abstinence are simply the Church’s specification of this divine requirement, made in keeping with Jesus giving the church the power to bind and loose (Matt. 16:18, 18:18).
Thus, one must substantially observe the law of abstinence on such days, and the obligation to do so is a grave one, meaning that it satisfies the condition of grave matter required for mortal sin. If one knowingly and deliberately fails in this obligation then one has committed mortal sin.
© Fr. Chinaka Justin Mbaeri, OSJ
Paroquia Nossa Senhora de Fatima, Vila Sabrina, São Paulo, Brazil
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