There were shepherds in the same country staying in the field, and keeping watch by night over their flock.
By night ...  Appropriately, Jesus was born at night; for there was a darker night symbolized by that event.  The scepter had about departed from Judah; the savage Idumean was on the throne of David; pagan darkness engulfed the world; and the lord of the whole world was the first of the Caesars, Augustus, whose successors would drown the world in blood, debauch the government, and usher in the age of darkness.  Beyond the confines of the ancient empire, the long and shameful gloom had settled over all the world; all nations sat in darkness.