‘As we begin Lent this week, I’ll be reposting condensed versions of previous entries in which I share thoughts on fasting from spiritual masters, from St. Francis de Sales to Dorothy Day.
All of the previous posts are linked here. What I’ll do this week is share briefer versions. Starting with St. Francis:

The whole, original post is here.
To treat of fasting and of what is required to fast well, we must, at the start, understand that of itself fasting is not a virtue. The good and the bad, as well as Christians and pagans, observe it. The ancient philosophers observed it and recommended it. They were not virtuous for that reason, nor did they practice virtue in fasting. Oh, no, fasting is a virtue only when it is accompanied by conditions which render it pleasing to God. Thus it happens that it profits some and not others, because it is not undertaken by all in the same manner.
…The first condition is that we must fast with our whole heart, that is to say, willingly, whole-heartedly, universally and entirely.…
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This is what the Church wishes to signify during this holy time of Lent, teaching us to make our eyes, our ears and our tongue fast. For this reason she omits all harmonious chants in order to mortify the hearing; she no longer says Alleluia, and clothes herself completely in somber and dark colors. And on this first day she addresses us in these words: Remember, man, that you are dust, and to dust you shall return [Gen. 3:19], as if she meant to say: “Oh man, quit at this moment all joys and merrymaking, all joyful and pleasant reflections, and fill your memory with bitter, hard and sorrowful thoughts. In this way you will make your mind fast together with your body.”
This is also what the Christians of the primitive Church taught us when, in order to spend Lent in a better way, they deprived themselves at this time of ordinary conversations with their friends, and withdrew into great solitude and places removed from communication with people……
The second condition is never to fast through vanity but always through humility. If our fast is not performed with humility, it will not be pleasing to God…
…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...
The third condition necessary for fasting well is to look to God and to do everything to please Him..
And as he summarizes:
This is all that I had to tell you regarding fasting and what must be observed in order to fast well. The first thing is that your fast should be entire and universal; that is, that you should make all the members of your body and the powers of your soul fast: keeping your eyes lowered, or at least lower than ordinarily; keeping better silence, or at least keeping it more punctually than is usual; mortifying the hearing and the tongue so that you will no longer hear or speak of anything vain or useless; the understanding, in order to consider only holy and pious subjects; the memory, in filling it with the remembrance of bitter and sorrowful things and avoiding joyous and gracious thoughts; keeping your will in check and your spirit at the foot of the crucifix with some holy and sorrowful thought. If you do that, your fast will be universal, interior and exterior, for you will mortify both your body and your spirit. The second condition is that you do not observe your fast or perform your works for the eyes of others. And the third is that you do all your actions, and consequently your fasting, to please God alone, to whom be honor and glory forever and ever.
“…the memory, in filling it with the remembrance of bitter and sorrowful things and avoiding joyous and gracious thoughts…”
That there must be the most foreign-to-the-modern-mindset item I have ever read. And by “modern” I don’t mean “kids these days who should stay off my lawn,” I mean that I can’t imagine this being thought of or advised by any person now living. Not that that’s bad, it’s just… foreign and thus food for thought.