“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  resence of the angelic powers and because of the reverence due to the sacred offering; for as the angels are said to have stood by the Lord’s body when it 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 consecration.”
(St Bede the Venerable in St Luke Commentary)

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