Why Have A Devotion to St. Michael?
The Benedictine Sisters of Perpetual Adoration in a 2006 book published by Tan Books answered this question well:
According to the great St. Alphonsus Liguori, veneration of the holy Angels, and particularly of St. Michael, is an outstanding sign of predestination. St. Lawrence Justinian says: "Although we must honor all the Angels, we ought to invoke in a very special manner the glorious St. Michael, as the Prince of all the heavenly spirits, because of his sublime dignity, his pre-eminent office and his invincible power, which he proved in his conflict with Satan, as well as against the combined forces of Hell." Again, the same Saint says: "Let all acknowledge St. Michael as their protector, and be devoted to him, for he cannot despise those who pray to him . . . But he guards them through life, directs them on their way and conducts them to their eternal home."
What is St. Michael's Lent?
St. Bonaventure records in his biography (written between 1260-1266) how St. Francis of Assisi, “was brought after many and varied toils unto a high mountain apart, that is called Mount Alverna. When, according unto his wont he began to keep a Lent there, fasting, in honor of St. Michael Archangel, he was filled unto overflowing, and as never before, with the sweetness of heavenly contemplation.”
The Little Flowers of St. Francis, a collection of stories about St. Francis that was compiled during the 13th century, records these words of St. Francis to his brothers, “My sons, we are drawing nigh to our forty days’ fast of St. Michael the Archangel; and I firmly believe that it is the will of God that we keep this fast in the mountain of Alvernia, the which by Divine dispensation hath been made ready for us, to the end that we may, through penance, merit from Christ the consolation of consecrating that blessed mountain to the honor and glory of God and of His glorious mother, the Virgin Mary, and of the holy angels.”
Fasting for St. Michael's Lent:
This fasting period begins on the Assumption (August 15) and ends on the feast of St. Michael (September 29). It excludes Assumption Day itself and all Sundays, which are never days of fasting although they may be days of abstinence if one so chooses to keep them as such.
Since this is a purely devotional fast, there is no historical basis to go off of, like we have with Lent, the Assumption Fast, etc. Using the standard for 1 meal, 1 frustulum, and 1 collation would be a good rule to follow here too.
I'd recommend adding, if you don't already, Wednesdays and Saturdays (in addition to Fridays) as days of abstinence.
Prayers for St. Michael's Lent
The SSPX Chapel in Oak Park, IL, recently distributed an excellent brochure featuring prayers to say each day of St. Michael's Lent. Those prayers are available as a scanned PDF by clicking here. Print them off and plan to say them each day for this period of penance. May God, through St. Michael, drive out from his Church and from all baptized souls any taint from the evil one.
Resources:
- St. Michael’s Lent: A period of fasting observed by St. Francis of Assisi published on Aleteia
- St. Michael's Lent Prayers & Devotions in the Exodus 90 App
- St. Michael's Lent Facebook Support Group