When angels appeared to shepherds one night over 2,000 years ago, they did so to announce something amazing: the Savior of the world has been born. But what else can we learn from this angelic visit? Let's take a look at some of our resources to find out.
[From the international standard bible encyclopedia]
(1) The Visit of the Shepherds.
To shepherds watching their flocks by night in the fields near Bethlehem the first disclosure was made. The season, one would infer, could hardly have been winter, though it is stated that there is frequently an interval of dry weather in Judea between the middle of December and the middle of February, when such a keeping of flocks would be possible (Andrews). The angel world is not far removed from us, and as angels preannounced the birth of Christ, so, when He actually came into the world (compare Hebrews 1:6), angels of God made the night vocal with their songs. First, an angel appearing in the midst of the Divine glory--the "Shekinah"--announced to the sorely alarmed shepherds the birth of a "Saviour who was Christ the Lord" at Bethlehem; then a whole chorus of the heavenly host broke in with the refrain, "Glory to God in the highest, and on earth peace among men in whom He is well pleased" (literally, "men of good pleasure")--since, the Christmas hymn of the generations (Luke 2:1). The shepherds, guided as to how to recognize the babe (Luke 2:12), went at once, and found it to be ever, as they had been told. Thence they hastened to spread abroad the tidings--the first believers, the first worshippers, the first preachers (Luke 2:15). Mary cherished the sayings in the stillness of her heart.
Some poor men who were faithfully performing their toilsome labours, afar from the restless activity of an ambitious and sinful world, receive the first tidings of the Lord's presence on earth. The God of Israel did not seek for the great among His people, but had respect to the poor of the flock. Two things here present themselves. The angel who comes to the shepherds of Judea announces to them the fulfilment of the promises of God to Israel. The choir of angels celebrate in their heavenly chorus of praise all the real import of this wondrous event.