St. Robert Bellarmine
The Art of Dying Well
Chapter 8: The Eighth Precept, on Fasting. · Part 2 of 2
Nor do those derive any fruit who, although they may eat more moderately, yet on fasting-days do not abstain from games, parties, quarrels, dissensions, lascivious songs, and immoderate laughter; and what is still worse, commit the same crimes as they would on ordinary days. Hear what the prophet Isaiah says of such kind of people: " Behold in the day of your fast your own will is found, and you exact of all your debtors. Behold you fast for debates and strife, and strike with the fist wickedly. Do not fast as you have done until this day, to make your cry to be heard on. high." (chap. lviii.) Thus does the Almighty blame the Jews, because on the days of their fasting, which were days of penance, they wished to do their own will and not the will of God; because they were not only not willing to forgive their debtors, (as they prayed to be forgiven by God.) but they would not even give them any time to collect their money. They also spent that time which ought to have been devoted to prayer, in profane quarrels, and even in contentions. In fine, so far were they from attending to spiritual things, as they ought to have done on the fasting-days, they added sin to sin, and impiously attacked their neighbours. These and other such sins ought those pious people to avoid, who wish their fasting to be pleasing unto God, and useful to themselves: they may then hope to live well, and die a holy death.
There now remain "almsdeeds," one of the three good works recommended to our imitation by the angel Raphael.
Source: The Art of Dying Well (Wikisource)