My soul magnifieth Here Mary testifies her gratitude, as we have already said. But as hypocrites, for the most part, sing the praises of God with open mouth, unaccompanied by any affection of the heart, Mary says that she praises God from an inward feeling of the mind. And certainly they who pronounce his glory, not from the mind, but with the tongue alone, do nothing more than profane his holy name. The words soul and spirit are used in Scripture in various senses, but, when employed together, they denote chiefly two faculties of the soul; spirit being taken for the understanding, and soul for the seat of the affections. To comprehend the meaning of the holy virgin, it must be observed that what is here placed second is first in order; for the excitement of the will of man to praise God must be preceded by a rejoicing of the spirit, [1] as James says, "Is any merry? let him sing psalms," (James 5:13.) Sadness and anxiety lock up the soul, and restrain the tongue from celebrating the goodness of God. When the soul of Mary exults with joy, the heart breaks out in praising God. It is with great propriety, in speaking of the joy of her heart, that she gives to God the appellation of Savior Till God has been recognised as a Savior, the minds of men are not free to indulge in true and full joy, but will remain in doubt and anxiety. It is God's fatherly kindness alone, and the salvation flowing from it, that fill the soul with joy. In a word, the first thing necessary for believers is, to be able to rejoice that they have their salvation in God. The next ought to follow, that, having experienced God to be a kind Father, they may "offer to him thanksgiving," (Psalm 50:14.) The Greek word soter, Savior, has a more extensive signification than the Latin word Servator; for it means not only that he once delivers, but that he is "the Author of eternal salvations" (Hebrews 5:9.)

Footnotes

1 - "Car avant que la volonte de l' homme soit mise en train de louer Dieu, il faut qu'il y ait devant une alaigrete et resiouissance d'esprit." -- "For before the will of man is set agoing to praise God, there must be previously a cheerfulness and rejoicing of spirit."

My soul doth magnify the Lord - To "magnify" means to "make great," and then to "extol," to "praise," to "celebrate." It does not mean here strictly to "make great," but to increase "in our estimation" - that is, to praise or extol. See Psalm 34:3; 2-Samuel 7:26.

And Mary said - Two copies of the Itala, and some books mentioned by Origen, give this song to Elisabeth. It is a counterpart of the song of Hannah, as related in 1-Samuel 2:1-10.
This is allowed by many to be the first piece of poetry in the New Testament; but the address of the angel to Zacharias, Luke 1:13-17, is delivered in the same way; so is that to the virgin, Luke 1:30-33, and so also is Elisabeth's answer to Mary, Luke 1:42-45. All these portions are easily reducible to the hemistich form in which the Hebrew poetry of the Old Testament is found in many MSS., and in which Dr. Kennicott has arranged the Psalm, and other poetical parts of the Sacred Writings. See his Hebrew Bible.
My soul doth magnify the Lord - The verb μεγαλυνειν, Kypke has proved, signifies to celebrate with words, to extol with praises. This is the only way in which God can be magnified, or made great; for, strictly speaking, nothing can be added to God, for he is infinite and eternal; therefore the way to magnify him is to show forth and celebrate those acts in which he has manifested his greatness.

(5) And Mary said, My soul doth magnify the Lord,
(5) Christ, the redeemer of the afflicted and revenger of the proud, promised long ago to the fathers, is now finally exhibited indeed.

And Mary said, my soul doth magnify the Lord. Either Jehovah, the Father, or the Son; who, as he was David's Lord, according to his divine nature, though his son after the flesh, was, in the same sense, Mary's Lord, as well as her son: and by "magnifying" him is meant, not making him great, for he cannot be made greater than he is; but ascribing greatness to him, even all the perfections of the Deity, and praising him on account of them; and also declaring and speaking well of his many and mighty works of power, goodness, grace, and mercy, and giving him the glory of them: this Mary did, not in lip and word only, but with her whole heart and, soul, and with all the powers and faculties of it; being filled with the Holy Ghost, and under a more than ordinary influence of his, as her cousin Elisabeth was: and it is to be observed, that she all along speaks in the prophetic style, of things, as if they were done, which were doing, or would shortly be done.

A magnificent canticle, in which the strain of Hannah's ancient song, in like circumstances, is caught up, and just slightly modified and sublimed. Is it unnatural to suppose that the spirit of the blessed Virgin had been drawn beforehand into mysterious sympathy with the ideas and the tone of this hymn, so that when the life and fire of inspiration penetrated her whole soul it spontaneously swept the chorus of this song, enriching the Hymnal of the Church with that spirit-stirring canticle which has resounded ever since from its temple walls? In both songs, those holy women, filled with wonder to behold "the proud, the mighty, the rich," passed by, and, in their persons the lowliest chosen to usher in the greatest events, sing of this as no capricious movement, but a great law of the kingdom of God, by which He delights to "put down the mighty from their seats and exalt them of low degree." In both songs the strain dies away on CHRIST; in Hannah's under the name of "Jehovah's King"--to whom, through all His line, from David onwards to Himself, He will "give strength"; His "Anointed," whose horn He will exalt (1-Samuel 2:10); in the Virgin's song, it is as the "Help" promised to Israel by all the prophets.
My soul . . . my spirit--"all that is within me" (Psalm 103:1).

Mary said. Mary also is filled with the spirit of prophecy. These two godly women are the first human prophets of the New Testament. Mary's language is in part drawn from the Psalm. This hymn is divisible into three parts: (1) Luke 1:46-49, recognition of God's strange grace upon her own humble person and character; (2) Luke 1:50-53, a recognition that it is ever thus that God exalts the humble, and brings low the proud; (3) Luke 1:54-55, the result is that humble Israel is now to be exalted according to God's ancient promise to Abraham.
My Saviour. Mary, by this word, reckons herself among that which was lost. She obtained salvation, not from herself, but from Jesus.--Bengel.
Call me blessed. Pronounce me highly favored, or happy in being the mother of the Messiah. Abraham was blessed in being the father of the faithful; Paul in being the apostle to the Gentiles; Peter in first preaching the gospel to them; but who would think of worshiping or praying to Abraham, Paul, or Peter?
To Abraham. See Genesis 12:1-3; Genesis 13:14-17; Genesis 15:5.
And his seed. The seed promised to Abraham was to be a blessing to the whole world. Compare the hymn of Hannah (1-Samuel 2:1).

And Mary said - Under a prophetic impulse, several things, which perhaps she herself did not then fully understand.