He found man reduced to the level of the beasts: therefore is He placed like fodder in a manger, that we, having left off our bestial life, might mount up to that degree of intelligence which befits man's nature; and whereas we were brutish in soul, by now approaching the manger, even His own table, we find no longer fodder, but the bread from heaven, which is the body of life. 

For this holy mystery was wrought with a wisdom most befitting Christ, if it be true, as true most certainly it is, that the Lord, though He is God, appeared unto us, and though He is in the form of God the Father, and possesses an incomparable and universal pre-eminence, took the likeness of a slave. But even so He was God and Lord; for He did not cease to be that which He had been. ... the rational powers of heaven bring the glad tidings of His manifestation and appearance in this world, to shepherds first of all at Bethlehem, who were thus the earliest to receive the knowledge of the mystery. And the type answers to the truth: for Christ reveals Himself to the spiritual shepherds, that they may preach Him to the rest, just as the shepherds also then were taught His mystery by the holy angels, and ran to bear the glad tidings to their fellows. Angels therefore are the first to preach Him, and declare His glory as God born in the flesh in a wonderful manner of a woman.
When therefore thou seest the child wrapped in swaddling-clothes, stay not thy thought solely upon His birth in the flesh, but mount up to the contemplation of His godlike glory: elevate thy mind aloft: ascend to heaven: so wilt thou behold  Him in the highest exaltation, possessed of transcendent glory; thou wilt see Him "set upon a throne high and lifted up;" thou wilt hear the Seraphim extolling Him in hymns, and saying that heaven and earth are full of His glory. Yea! even upon earth this has come to pass: for the glory of God shone upon the shepherds, and there was a multitude of the heavenly armies telling Christ's glory. 

Additional information