In the fifth century, the 29th day of September, coinciding with the anniversary of the Dedication of several important churches under the invocation of St. Michael the Archangel, began to be regarded as an appropriate day for the yearly solemn commemoration of the Holy Angels. It soon thereafter became of universal celebration as a high festival. Of the Holy Angels, who are numbered by millions (Daniel 7:10) holy Church venerates, in an especial manner, besides St. Michael their Prince, Saints Gabriel (March 18) and Raphael (October 24), of whom names have been revealed to us, and those who have been appointed to be the particular Guardians of men (October 2 - Holy Guardian Angels).
From the Roman Missal, Seventh Edition, Benziger Brothers, 1936.
