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And lo, the angel of the Lord,.... It may be Gabriel, who had brought the tidings of the conception of the Messiah to the virgin, and now the birth of him to the shepherds:

came upon them; on a sudden, unexpectedly, at once, and stood by them, as some versions read; or rather, stood over them, over their heads, just above them; so that he was easily and perfectly seen by them;

and the glory of the Lord shone round about them; or a very glorious and extraordinary light shone with surprising lustre and brightness all around them; by which light, they could discern the illustrious form of the angel that was over them:

and they were sore afraid; at the sight of such a personage, and at such unusual light and glory about them: they were not used to such appearances, and were awed with the majesty of God, of which these were symbols, and were conscious to themselves of their own sinfulness and frailty.

The glory of the Lord - This is the same as a “great” glory - that is, a splendid appearance or “light.” The word “glory” is often the same as light, 1 Corinthians 15:41; Luke 9:31; Acts 22:11. The words “Lord” and “God” are often used to denote “greatness” or “intensity.” Thus, “trees of God” mean great trees; “hills of God,” high or lofty hills, etc. So “the glory of the Lord” here means an exceedingly great or bright luminous appearance perhaps not unlike what Paul saw on the way to Damascus.