Who are they? St. Augustine says: “‘Angel’ is the name of their office, not of their nature. If you seek the name of their nature, it is ‘spirit’; if you seek the name of their office, it is ‘angel’“ (Enarr. in Ps., 103, 1, 15). With their whole beings the angels are servants and messengers of God. Because they “always behold the face of my Father who is in heaven” they are the “mighty ones who do his word, hearkening to the voice of his word” (Ps 103:20).
Angel was the name of one of the bodyguards who travelled with St Josemaria during his visit to Argentina in 1974. He said what impressed him most was St Josemaria's concern for everyone around him. He said, "Meeting the Father was the best thing that ever happened to me."
On Thursday, October 6, 1932, while St Josemaria Escriva was praying in the chapel of Saint John of the Cross during his retreat at the Discalced Carmelite monastery in Segovia, he was for the first time inwardly moved to invoke the three archangels and the three apostles Saints Michael, Gabriel, and Raphael, and Saints Peter, Paul, and John. From that moment on he considered them the patrons of the different fields of apostolate that would make up Opus Dei.
"The Angel is a creature who stands before God, oriented to God with his whole being." From a homily by Benedict XVI given on September 29, 2007, feast of the three Archangels.