The following is taken from Mary, Hope of the World by Rev. James Alberione, S.T.D., St. Paul Editions
"Divine Providence, which guides everything with firmness and sweetness, was watching over the child Mary, and preparing her for the high position of Mother of God. Toward this end, by means of her parents, God led the heavenly child to the Temple of Jerusalem.
The Presentation in the Temple.
...Mary was scarcely three years old when accompanied by her parents, she first set foot in the Temple. Here the noble child was admitted to the elect group of virgins consecrated to God...
The purpose of Mary's presentation in the Temple was twofold: that she might consecrate herself to the Lord and receive a suitable spiritual formation..."
The following are quotes by the saints used by Father Alberione in his book:
"...Her mind was always absorbed in the Supreme Good. Her humility, her obedience and her modesty, which is a girl's most valuable asset, matched her silence. To use every minute of the day for the honor of God, she combined mental activity with manual labor. Her soul was never tempted to sloth, and necessity alone made her take repose. Even then, she kept watch in the presence of the supreme Goodness, dreaming of the glories of the lord and the wisdom of the divine word, which she had read during the day." - St. Ambrose
"Hardly had the Blessed Virgin entered the Temple when she imposed upon herself an admirable rule of life: from early morning until nine o'clock, she devoted herself to prayer; from nine until three in the afternoon she attended to external activities; then she returned to prayer until the Angel appeared to bring her daily bit of nourishment. She was as always the first at nocturnal vigils, she studied the Law of the Lord with more diligence than the others, she surpassed the most humble in humility;p Mary chanted David's songs with greater grace, she practised the works of charity with more fervor, she was the purest among the chaste, and she possessed all virtues in a grater degree. She was firm and constant, and every day she grew in grace and sweetness. Her words were all filled with grace, and when near her, people felt the presence of God. She was always at prayer and unceasingly meditated upon the Law of the Lord. She never ceased to bless God, and when she was greeted, instead of replying with the ordinary words of courtesy, she would reply, 'Thanks be to God.'" - St. Jerome
"This blessed child was most delicate; she loved the sacred truths and had herself fully instructed in them. She served the priests joyfully. Hers was the habit of speaking little and of obeying promptly. She was modest, serene, and full of sweetness. She greeted everyone with kindness, and her graciousness and beauty made her greatly admired." - St. Anselm