Bede the Venerable
Catena Aurea · Lukasevangelium 2
And there were in the same country shepherds abiding in the field, keeping watch over their flock by night. And, lo, the angel of the Lord came upon them, and the glory of the Lord shone round about them: and they were sore afraid. And the angel said unto them, Fear not: for, behold, I bring you good tidings of great joy, which shall be to all people. For unto you is born this day in the city of David a Saviour, which is Christ the Lord. And this shall be a sign unto you; Ye shall find the babe wrapped in swaddling clothes, lying in a manger.
(Hom. inter Hyem. de Sanctis v.) No where in the whole course of the Old Testament do we find that the Angels who so constantly appear to the Patriarchs, came with light. This privilege was rightly kept for this time when there arose in the darkness a light to them that were true of heart. Hence it follows, and the glory of God shone round about them. (Ps. 112:4.) He is sent forth from the womb, but He shines from heaven. He lies in a common inn, but He lives in celestial light.