In the four Gospels answer to the question "where" Jesus is from clearly emerges, his true origin is the Father, He comes entirely from Him, but in a different way from any prophet sent by God who preceded him. This originates in the mystery of God, who "no one knows", it is already contained in the infancy narratives of the Gospels of Matthew and Luke, which we are reading in this Christmas season. The angel Gabriel announces: "The holy Spirit will come upon you, and the power of the Most High will overshadow you. Therefore the child to be born will be called holy, the Son of God"(Lk 1:35). We repeat these words every time we recite the Creed, the profession of faith: "et incarnatus est de Spiritu Sancto, ex Maria Virgine," "by the power of the Holy Spirit he was born of the Virgin Mary". In this sentence we bow our heads for the veil that hid God is, so to speak, lifted and his unfathomable and inaccessible mystery touches us directly: God becomes Emmanuel, "God with us."
When we listen to the Masses composed by the great masters of sacred music, I think of the example of Mozart's Great Mass, we immediately notice how they linger especially on this phrase, as if to try to express in the universal language of music that which words can not: the great mystery of God who becomes incarnate, who becomes man.