Ember days
The days of harvest in September included three forgotten days (Wednesday, Friday and Saturday, collectively called “Embertide”) observed by all Western Roman Catholics in the Medieval Period: Ember Days.
Today is Ember Wednesday of the Michaelmas Embertide–historically reserved by Christians for fasting and abstaining from meat (except the principle meal) leading up to the Feast of St. Michael the Archangel, which is celebrated September 29th. Embracing Embertide is one means of reclaiming a piece of Christian culture that has been lost in our time.
Christianization of pagan celebrations
Before the fall of the Roman Empire (which occurred in 410 AD), the Catholic Church sought not only to sanctify its people–but to set apart some of the once-pagan festivals as well. Harvest time and its seasonal festivals fit nicely with the days leading up to Michaelmas.
It was an opportunity for Christians to recognize, no matter how industrious their agricultural labors, mankind cannot control the elements, nor the quantity or quality of the fruits of his labor.
The observance was also an opportunity for petitioning to God for a bountiful harvest, recognizing with humility their dependence on His loving provision for their livelihood, and giving thanks for His generosity.
See source: https://www.catholic.com/encyclopedia/ember-days.
Incorruptible treasures
Although we are not accustomed to fasting from anything in the United States, this idea of “fasting before feasting” reminds us the treasures we attain here on earth–however desirable–are corruptible. We really long for the things of heaven, not the things of earth, which is passing away (Matt 24:35).
As St. Bede the Venerable (673-735 AD) put it, there are better things that await us when we sacrifice our selfish wants: the “incorruptible treasures [in] heaven.”
Source: Divine Office Beviary, Liturgy of the Hours, A Sermon from September 21, 2022, https://www.universalis.com/-400/readings.htm.
St. Matthew the Apostle, whose feast day it is today, pray for us.