Albert Barnes Commentary Luke 1:47

"And my spirit hath rejoiced in God my Saviour." — Luke 1:47 (ASV)

In God my Saviour. God is called Saviour, as he saves people from sin and death. He was Mary's Saviour, as he had redeemed her soul and given her a title to eternal life; and she rejoiced for that, and especially for his mercy in honouring her by her being made the mother of the Messiah.