God gave his Son to Mary for the world to receive him from her

"The world being unworthy," said Saint Augustine, "to receive the Son of God directly from the hands of the Father, he gave his Son to Mary for the world to receive him from her."

The Son of God became man for our salvation but only in Mary and through Mary.

God the Holy Spirit formed Jesus Christ in Mary but only after having asked her consent through one of the chief ministers of his court.

God the Father imparted to Mary his fruitfulness as far as a mere creature was capable of receiving it, to enable her to bring forth his Son and all the members of his mystical body.

God the Son came into her virginal womb as a new Adam into his earthly paradise, to take his delight there and produce hidden wonders of grace.

God-made-man found freedom in imprisoning himself in her womb. He displayed power in allowing himself to be borne by this young maiden. He found his glory and that of his Father in hiding his splendors from all creatures here below and revealing them only to Mary… It was Mary who nursed him, fed him, cared for him, reared him, and sacrificed him for us.

Saint Louis de Montfort

Treatise on True Devotion to the Blessed Virgin, Chapter 1, § 16-18