St. Francis de Sales on Fasting:
The glorious St. Augustine, in the Rule that he wrote for his religious (later adapted for men religious), orders that one follow the community as much as possible, as if he wished to say: Do not be more virtuous than the others; do not wish to practice more fasting, more austerities, more mortifications than are ordered for you. Do only what the others do and what is commanded by your Rule, according to the manner of living that you follow, and be content with that. For although fasting and other penances are good and laudable, nevertheless, if they are not practiced by those with whom you live, you will stand out and there will be some vanity, or at least some temptation to esteem yourself above others. Since they do not do as you do, you experience some vain complacency, as if you were more holy than they in doing such things.
Follow the community then in all things, said the great St. Augustine. Let the strong and robust eat what is ordered them, keeping the fast and austerities which are marked, and let them be content with that. Let the weak and infirm receive what is offered them for their infirmity, without wishing to do what the robust do. Let neither group amuse themselves in looking to see what this one eats and what that one does not eat, but let each one remain satisfied with what she has and with what is given to her. By this means you will avoid vanity and being particular.
