10 We must not omit to mention another excellence of this Sodality. As often as, in reciting the Rosary, we meditate upon the mysteries of our Redemption, so often do we in a manner emulate the sacred duties once committed to the Angelic hosts. The Angels revealed each of these mysteries in its due time; they played a great part in them; they were constantly present at them, with countenances indicative now of joy, now of sorrow, now of triumphant exultation. Gabriel was sent to announce the Incarnation of the Eternal Word to the Virgin. In the cave of Bethlehem, Angels sang the glory of the new-born Saviour. The Angel gave Joseph command to fly with the Child into Egypt. An Angel consoled, with his loving words, Jesus in His bloody sweat in the garden. Angels announced His resurrection, after He had triumphed over death, to the women. Angels carried Him up into Heaven; and foretold His second coming, surrounded by Angelic hosts, unto whom He will associate the souls of the elect, and carry them aloft with Him to the heavenly choirs, "above whom the Holy Mother of God is exalted." To those, therefore, who make use of the pious prayers of the Rosary in this Sodality, may be well applied the words with which St. Paul addressed the new Christians: "You are come to Mount Sion, and to the city of the living God, the Heavenly Jerusalem, and to the company of many thousands of Angels" (Heb. xii., 22). What more divine, what more delightful, than to meditate and pray with the Angels? With what confidence may we not hope that those who on earth have united with the Angels in this ministry will one day enjoy their blessed company in Heaven?
Source: Augustissimae Virginis Mariae (Vatican.va)