"Now Mary arose in those days and went into the hill country with haste, to a city of Judah, and entered the house of Zacharias and greeted Elizabeth. And it happened, when Elizabeth heard the greeting of Mary, that the babe leaped in her womb; and Elizabeth was filled with the Holy Spirit. Then she spoke out with a loud voice and said, 'Blessed are you among women, and blessed is the fruit of your womb! But why is this granted to me, that the mother of my Lord should come to me? For indeed, as soon as the voice of your greeting sounded in my ears, the babe leaped in my womb for joy. Blessed is she who believed, for there will be a fulfillment of those things which were told her from the Lord'" (Luke 1:39-45).
Luke records that Mary left soon after speaking with Gabriel and traveled quickly to the house of Zacharias, to visit her relative Elizabeth (in order to share the joyful news, of course). At this point, both women are pregnant: Mary with Jesus, and Elizabeth with John (who would be known later as John the baptizer). John leaped in Elizabeth's womb and "Elizabeth was filled with the Holy Spirit" (cf. 1:15). At that moment she possessed some supernatural knowledge and prophesied to Mary. Elizabeth spoke in a loud voice, indicating her intense joy. She knew of Mary's conception, though her pregnancy would not have been "showing" yet at that point. She also knew that Mary would be the mother of not just any child, but the mother of the Lord! Elizabeth feels honored that she was found to be worthy of a visit from such a woman. Finally, Elizabeth declared - "Blessed is she who believed." Unlike Zacharias (cf. 1:18-20), Mary believed the news that Gabriel delivered (and the divine announcement of Jesus' conception required far more faith than that of John's). Elizabeth has high praise for the faith of Mary! That which the Lord had revealed would most certainly come to pass!
In response, Mary breaks forth in a song of praise and joy (cf. Hannah's song - I Sam. 2:1-10). This section comprises most of the spoken material we have recorded of Mary:
"My soul magnifies the Lord, and my spirit has rejoiced in God my Savior. For He has regarded the lowly state of His maidservant; for behold, henceforth all generations will call me blessed. For He who is mighty has done great things for me, and holy is His name. And His mercy is on those who fear Him from generation to generation. He has shown strength with His arm; He has scattered the proud in the imagination of their hearts. He has put down the mighty from their thrones, and exalted the lowly. He has filled the hungry with good things, and the rich He has sent away empty. He has helped His servant Israel, in remembrance of His mercy, as He spoke to our fathers, to Abraham and to his seed forever" (Luke 1:47-55).
Mary speaks of "God my Savior," which is a reference here to the Father (cf. I Tim. 1:1; Titus 3:4) and acknowledges the great things He has done for her. Truly, all generations are blessed and should be grateful for Jesus Christ and His mother Mary (cf. Gen. 22:18). Mary should be highly honored, though she is not to be worshiped (cf. Rom. 1:25; Matt. 12:46-50; Luke 11:27,28). No mere mortal is worthy of being worshiped, no matter what role they may play in God's scheme of redemption.
Mary goes on to praise God's holiness (cf. Lev. 11:45) and His unceasing mercy (to those who love and obey Him, cf. Exo. 20:6). She transitions into a general song of praise as she rises above personal blessings and focuses on the divine glory and goodness of God. Some of the expressions she uses are vivid and powerful ("scattered the proud", "put down the mighty", "exalted the lowly", etc.). These are all expressions to communicate the disappointment of the proud, the princely, and the rich, in whose families the Messiah was expected. God has passed these by, and exalted a lowly one--like Mary. Even today God often works in ways that conflict with man's expectations (cf. I Cor. 1:18-25): The way to be great is to serve (cf. Matt. 20:27), the way to live is to die (cf. Matt. 16:25), the way to be exalted is to be humble (cf. James 4:10), etc. Mary praises the Lord for this paradox! Mary understood that the coming of the Messiah was a demonstration of God's mercy and faithfulness (i.e., the fulfilling of His promise to Abraham and his descendants; cf. Gen. 12:1-3).
It appears that Mary left Elizabeth and returned to her own home just prior to John's birth (although it is difficult to know for certain). She had been there "about three months" (Luke 1:56).