In the Magnificat, Mary refers to God as her Savior. According to Roman Catholic doctrine, Mary was born sinless and remained sinless throughout her life.
So, why does Mary refer to God as her Savior if she was sinless (and therefore would not have need of a Savior or even have one).
And Mary said:
“My soul exalts the Lord, And my spirit has rejoiced in God my Savior. For He has had regard for the humble state of His bondslave; for behold, from this time on all generations will count me blessed. For the Mighty One has done great things for me; and holy is His name. And His mercy is upon generation after generation Toward those who fear Him. He has done mighty deeds with His arm; He has scattered those who were proud in the thoughts of their heart. He has brought down rulers from their thrones, And has exalted those who were humble. He has filled the hungry with good things; And sent away the rich empty-handed. He has given help to Israel His servant, In remembrance of His mercy, As He spoke to our fathers, To Abraham and his descendants forever.” (Luke 1:46-55)