“Bless the Lord, all you his angels, mighty in power, fulfilling his word, and heeding his voice.” Psalm 103: 20
“Some angels are given proper names to denote the service they are to perform. In that holy city, where perfect knowledge flows from the vision of almighty God, those who have no names may easily be known. But personal names are assigned to some, not because they could not be known without them, but rather to denote their ministry when they come among us. Thus, Michael means ‘Who is like God?’; Gabriel is ‘The Strength of God’; and Raphael is ‘God’s Remedy.’”
Saint Gregory the Great, Homily 34 on the Gospels.