Whenever we enter the church and draw near to the heavenly Mysteries, we ought to Approach with all humility and fear, both because of the presence of the Angelic powers and out of reverence due to the Sacred Oblation; for as the angels are said to have stood by the Lord’s body when He lay in the tomb, so we must believe that they are present in the celebration of the Mysteries of His most Sacred Body at the time of the consecration.
St. Bede the Venerable