The Christmas story is filled with angels, from the angel Gabriel to the angel who appeared to the shepherds. The word angel means messenger and angels are used as such by God. So often when angels appear in scripture, nearly the first words they say are, "do not be afraid". This leads me to believe that they are not the sweet feminine creatures that we tend create, but instead must be rather terrifying.
In the sixth month the angel Gabriel was sent from God to a city of Galilee named Nazareth, to a virgin betrothed to a man whose name was Joseph, of the house of David; and the virgin's name was Mary. And he came to her and said, "Hail, O favored one, the Lord is with you!" But she was greatly trouble at the saying and considered in her mind what sort of greeting this might be. And the angel said to her, "Do not be afraid, Mary, for you have found favor with God. And behold, you will conceive in your womb and bear a son, and you shall call his name Jesus."
And in that region there were shepherds out in the field, keeping watch over their flock by night. And an angel of the Lord appeared to them, and the glory of the Lord shone around them, and they were filled with fear. And the angel said to them, "Be not afraid; for behold, I bring you good news of a great joy which will come to all the people; for to you is born this day in the city of David a Savior, who is Christ the Lord. And this will be a sign for you: you will find a babe wrapped in swaddling cloths and lying in a manger." And suddenly there was with the angel a multitude of the heavenly host praising God ad saying,
"Glory to God in the highest,
and on earth peace among men with whom he is pleased!"