Wednesday, Friday and Saturday are known as Ember days and are days of particular prayer and fasting. Four times in the year these Ember days are celebrated, and in the Advent Season their particular focus is to prepare ourselves spiritually - and physically - for the coming feast - and feasting - of Christmas.
In Adventus30 and in Septuagesima70 before it we have laid out different ‘levels’ of fasting that each adherent is free to adopt as a way of living these fast days. Nowadays it is nothing to hear about, in physical fitness contexts, the power and wonders of intermittent fasting, where some of the regimes can last for three or four days on only water (and coffee). All of this came from the Church who has seen the many benefits of fasting live well for the soul, and enjoyed them also for the body.
So we have our three levels. The first is perhaps the most difficult, and if you cannot do it on each of the days, you may like to do it on or other of these Ember days coming. The first level is to fast on bread and water. While the bread and the water can be sustaining, nevertheless they have no taste and so a great deal of our own preferences and taste die with this particular form of fasting.
If this fasting is too difficult the Church has at different times, and like the Muslims, recommended that no food is taken at all during the day until sundown. This is a slightly less rigorous fast but significant nonetheless.
Finally there is the possibility of what the Church recommends as a minimum: Skipping one of the meals of the day in fasting.
Adventus30 adherents are free to make their own choice about what ‘level’ of fasting they will take on for all (or some) of the Ember days whilst bearing in mind that the Church has great need of the benefits that these penitential practices provide and encourages us to do that little bit more in reparation for our own sins, the sins of our neighbour, and indeed the sins of the whole world.
For those who would like to read a bit more about the history of the Ember days I would recommend fisheaters.com explanation: https://www.fisheaters.com/emberdays.html and https://www.fisheaters.com/customsadvent11.html
A blessed continuing of Advent to all,