“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.”
Luke 2:9 — Greek Interlinear
Church Fathers on Luke 2:9
Observe with what care God builds up our faith. An Angel teaches Mary; an Angel teaches Joseph; an Angel the shepherds also, of whom it is said, And there were in the same country shepherds abiding in the field.
To Joseph the Angel appeared in a dream, as to one who might be easily brought to believe, but to the shepherds in visible shape as to men of a ruder nature. But the Angel went not to Jerusalem, sought not for Scribes and Pharisees, (for they were corrupt and tormented with envy.) But these were simple men living in the ancient practices of Moses and the Patriarchs. There is a certain road which leads by innocence to Philosophy.
No where; in the whole course of the Old Testament do we find that the Angels who so constantly appear to the Patriarchs, came in the day time. This privilege was rightly kept for this time, when there arose in the darkness a light to them that were s true of heart. Hence it follows, and the glory of God shone round about them. He is sent forth from the womb, but He shines from heaven. He lies in a common inn, but He lives in celestial light.