21 And so these two very singular privileges, bestowed upon the Virgin Mother of God, stand out in most splendid light as the beginning and as the end of her earthly journey; for the greatest possible glorification of her virgin body is the complement, at once appropriate and marvelous, of the absolute innocence of her soul, which was free from all stain; and just as she took part in the struggle of her only-begotten Son with the wicked serpent of Hell, so also she shared in His glorious triumph over sin and its sad consequences.
Source: Fulgens Corona (Vatican.va)