Saint Augustine (354-430) teaches that Mary first conceived the Verb in her heart through faith, before she conceived him in her womb. This birth of the Verb through faith heralds the birth of Jesus in the souls of those who believe in him as the One sent by the Father.
This is why Saint Ambrose of Milan (d. 397) gave the newly baptized the name of “Mary”. The soul of every Christian begets Jesus through faith, after Mary's example: "Every believing soul (like Mary) conceives and gives birth to the Word of God... According to the flesh, there is only one Mother of Christ; according to faith, Christ is the fruit of all"; "When this soul begins to convert to Christ, its name is Mary: that is, it receives the name of the one who gave birth to Christ: it has become a soul that begets Christ in a spiritual way".
Through faith, the Christian soul becomes the mother of God under the action of the Holy Spirit. The soul’s "first name" therefore is “Mary”.