This is a beautiful and very meaningful title of Our Lady.  The sorrow brought into the world by Eve’s disobedience has been changed into joy by the obedience of the New Eve, the Blessed Virgin Mary.  The prophet Zechariah foretold this as he spoke God’s words that we heard in our first reading:  “Sing and rejoice, O daughter of Zion!  See, I am coming to dwell among you, says the Lord.”  The angel Gabriel repeated this call to rejoice when he spoke to Mary at the Annunciation and told her she was to conceive the Messiah, the Son of God.

This great joy was communicated by Mary to Elizabeth at the Visitation.  At that joyful encounter, even the unborn infant John the Baptist rejoiced.  As Saint Luke tells us, the infant John leapt for joy in his mother’s womb.  And Mary, on that occasion, sang the beautiful canticle of joy, the Magnificat, which we prayed as our responsorial psalm today.  We sing with Mary:  “My soul proclaims the greatness of the Lord; my spirit rejoices in God my Savior.”