"And blessed is she that believed: for there shall be a performance of those things which were told her from the Lord." Luke 1:45
"And Mary said, My soul doth magnify the Lord, and my spirit hath rejoiced in God my Saviour.
For He hath regarded the low estate of His handmaiden: for, behold, from henceforth all generations shall call me blessed.
For He that is mighty hath done to me great things; and Holy is His Name.
And His mercy is on them that fear Him from generation to generation.
He hath shewed strength with His arm; He hath scattered the proud in the imagination of their hearts.
He hath put down the mighty from their seats, and exalted them of low degree.
He hath filled the hungry with good things; and the rich He hath sent empty away.
He hath helped His servant Israel, in remembrance of His mercy; as He spake to our fathers, to Abraham, and to his seed for ever." Luke 1:46-55
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“Mary’s first sentence in the Magnificat is a model of heartfelt worship. Out of a surrendered life she lifts her entire inner being to exalt the covenant God who keeps His promises. Her example invites us to let every part of who we are magnify the Lord, spotlighting His greatness rather than our own and trusting Him to accomplish all He has declared.”
Summary from What Does Luke 1:46 Mean from BibleHub. Read more here
“It is remarkable how simply Scripture has met beforehand the monstrous unbelief of man which lowers God as much as it exalts a human being. Mary had no thought of exaltation. She says, "All generations shall call me blessed," but not a blesser. She was the object of blessing, not the giver or mediatrix of it. "For the Mighty One hath done to me great things; and holy [is] his name [not a word of her own]. And his mercy is to generations and generations* to them that fear him [not that pray to or worship me]. He hath wrought strength with his arm; he hath scattered haughty [ones] in the thought of their heart. He hath put down rulers from thrones, and exalted the lowly" - alluding to her own place as well as Elisabeth's. "He hath filled the hungry with good things; and sent the rich empty away. He hath helped Israel, his servant, in order to remember mercy; as he spoke to our fathers, to Abraham, and to his seed for ever." It is remarkable how Jewish the character of the joy is, and the acknowledgement of the mercy.”
William Kelly, from William Kelly Major Works Commentary Luke 1. Read more here