DEVOTION IV. OF FASTING.
Many servants of Mary, on Saturdays and the vigils of her feast, are accustomed to honor her by fasting on bread and water.
It is well known that Saturday is a day dedicated by the holy Church to the honor of the Virgin, because on this day, says St. Bernard, she remained constant in the faith after the death of her Son.
For this reason the servants of Mary never fail on this day to offer her some special homage; and particularly the fast on bread and water, as St. Charles Borromeo, Cardinal Toledo, and so many others practised it. Rittard, Bishop of Bamberg, and Father Joseph Arriaga, of the Society of Jesus, did not even taste food on Saturday.
The great graces which the mother of God afterwards bestowed upon those who practised this devotion, may be read in the writings of Father Auriemma. It is sufficient for us to mention the compassion which she showed to that bandit chief, who on account of this devotion, was permitted to remain alive, although his head had been cut off, and although he was under the displeasure of God, and was enabled to make his confession before dying. He afterwards declared that the holy virgin, for this fasting which he had offered her, had preserved him in life, and he then suddenly expired.
It would not then be a very extraordinary thing, if any one, especially devoted to Mary, and particularly if he had already deserved hell, should offer to her this fast on Saturday.
He who practises this devotion, I may say, will hardly be condemned; not that our Lady will deliver him by a miracle if he dies in mortal sin, as happened to the bandit; such prodigies of divine mercy seldom take place, and it would be madness to expect eternal salvation by them. But I do say that the divine mother will readily obtain perseverance in divine grace and a good death for him who will practise this devotion.
All the brothers of our little congregation who can do so, fast on bread and water on Saturday, in honor of Mary. I say those who can do so, meaning, that if any one is prevented from doing so on account of ill health, at least on Saturday, he may content himself with one dish, make a common fast, or at least abstain from fruits or other agreeable food.
It is necessary on Saturday to offer special devotions to our Lady, to receive communion, or, at least, hear mass, visit some image of the Virgin, wear hair-cloth, and the like.
And at least on the vigils of the seven feasts of Mary, let her servants endeavor to offer this fasting on bread, or in any other manner they are able.
Note from the editor of Immaculata Library:
It would be well to add here, that St. Francis de Sales might recommend doing undertaking labor for the glory of God and Mary instead of fasting:
Labour, as well as fasting, serves to mortify and subdue the flesh. Now, provided the labour you undertake contributes to the glory of God and your own welfare, I had rather you would suffer the pain of the labour than that of fasting.
This is the sense of the Church, since, on account of such labours as contribute to the service of God and our neighbour dispenses persons engaged in them, even from the fasts commanded.
Some find it painful to fast; others to serve the sick or visit prisoners; others to hear confessions, to preach, pray, and perform such like exercises.
These latter kind of pains are of more value than the former; for, besides subduing the body, they produce fruits much more desirable, and therefore, generally speaking, it is better to preserve our bodily strength more than may be necessary than to weaken it too much; for we can always decrease it when we will, but we cannot always repair it when we would desire to do so.
This is from his chapter The Exercise of Exterior Mortification, which contains other advice on proper fasting as well.