The Magnificat is the essence of true prayer

“During those days Mary set out and traveled to the hill country in haste to a town of Judah, where she entered the house of Zechariah and greeted Elizabeth. When Elizabeth heard Mary’s greeting, the infant leaped in her womb, and Elizabeth, filled with the Holy Spirit, cried out in a loud voice and said, “Most blessed are you among women, and blessed is the fruit of your womb. And how does this happen to me, that the mother of my Lord* should come to me? For at the moment the sound of your greeting reached my ears, the infant in my womb leaped for joy. Blessed are you who believed* that what was spoken to you by the Lord would be fulfilled.”

Mary then said her magnificat, which the entire Church continues to repeat after her. Pope Emeritus Benedict XVI commented:

"[The Magnificat of Mary] is a prayer of thanksgiving, of joy in God, of blessing for his mighty works. The tenor of this song is clear from its very first words: “My soul magnifies - makes great - the Lord”. Making the Lord great means giving him a place in the world, in our lives, and letting him enter into our time and our activity: ultimately this is the essence of true prayer. Where God is made great, men and women are not made small: there too men and women become great and the world is filled with light."

Pope Benedict XVI - Homily during Holy Mass in the square in front of the Shrine of Altötting (Bavaria, Germany) on September 11, 2006