To what did Mary ... assent, when she said to Gabriel, "Fiat mihi," "Let it happen to me"? Of course it was her womb that with these words she offered, to be God's space in the world. The whole history of Israel had been God's labour to take Israel as his space in the world. And it was indeed a labour, for Israel by her own account was a resistant people: again and again the Lord's angel announced his advent, begged indeed for space, and again and again Israel's answer was "Let it be, but not yet." Gabriel's mission to Mary was, so to speak, one last try, and this time the response did not temporize ...
"Fiat mihi," said Mary, giving her womb as space for God in this world. After all the Lord's struggle with his beloved Israel, he finally found a place in Israel that unbelief would not destroy like the Temple, or silence like the prophets, or simply lose, like the Book of the Law before Josiah. This place is a person.
~ Robert Jenson, "A Space for God" in Carl Braaten & Robert Jenson's Mary, Mother of God
H/t to Catholicity and Covenant for the quote