There is one word that defines for us, more than any other, how Mary responds to God’s plan for the redemption of the world and her indispensable role in it.
This is the Latin word for what in English is let it be done to me. This what Mary says in Luke 1:38, at the end of the Annunciation, in response to the promise that God would overshadow her and she would conceive God in the flesh.
The Church following the teaching of Pope St. John Paul II sees Mary’s fiat as both an exemplar of radical Christian humility as well as an indication of how she would cooperate with God in bringing about his redemption of mankind. As one scholar, Antonio Lopez, writes,
Mary’s faith, expressed in her fiat, is neither a simple acceptance nor a resignation before God’s will. Rather, ‘let it be done unto me’ expresses a joyful desire to collaborate (génoito) with whatever God has determined, even without fully understanding what this will means.
The Latin well captures Mary’s simple humility by expressing her response in a single word. Indeed, it is fitting that the single Word of God entered this world through a single word. We should expect such harmony given the reality of the Incarnation. As then-Cardinal Joseph Ratzinger observes in Mary: The Church at the Source: “Mary welcomes the Holy Spirit into herself. Having become pure hearing, she receives the Word so totally that it becomes flesh in her.”
This transformation culminates in Mary’s way of speech, which is shaped by the Word dwelling fully within her. The Church teaches that Christ constitutes the fullness of revelation—not the many words of Scripture, which are revelation, but are not revelation in its fullness. That is reserved for Christ, the Word Incarnate.
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