"Mother Teresa of Calcutta, renowned for the worldwide mission of charity that she began in 1946, used a simple "tool" as a symbol of that charity: the "Miraculous Medal." A common sight it was to watch Mother take a fistful of such medals, kiss them, and hand them out to the poor. Queues of people would form outside her convents when word would spread that Mother Teresa had come to town. One by one she would welcome young and old, the sick and the needy, lay and clergy, the significant and the insignificant. Rarely would any leave without Mother pressing Miraculous Medals into their hands.
Taking a Miraculous Medal in her knarled and toilworn fingers, Mother Teresa often would ask the sick person "Where does it hurt?"; then she would gently press the medal on that spot. "Let Our Lady kiss where it hurts," she would be heard to say. Then she would tell the sick person: "Repeat after me: ‘Mary Mother, be a mother to me NOW." She would stress the word "now," and repeat the phrase, as she caressed the sick with Our Lady's medal. For Mother Teresa, this was a "medal of charity", a sign of God's single interest in each and every person at each and every moment "now" of life. She gave to the Miraculous Medal a new apostolic thrust, and refocused the Medal's spirituality and theology through the prism of her holy mission of charity."
(Excerpt from article, Mother Teresa and the Miraculous Medal written by Fr. McCurry, O.F.M. Conv. in honour of the beatification of Mother Teresa, 19th October 2003.)