St. Maximilian Kolbe called the Miraculous Medal his "bullet" that he used as a spiritual weapon.

Even if someone is as wicked as can be, if he agrees to wear the Miraculous Medal, give it to him and pray for him, and occasionally try with a kind word to bring him to the point where he begins to love the Mother of God and to fly to her in all his difficulties and temptations. Anyone who sincerely begins to pray to the Immaculata will soon be convinced to go to Confession as well.

There is much evil in the world, yet let us consider that the Immaculata is even more powerful.

The Miraculous Medal was not only distributed by Kolbe, but was also worn by those in his religious order and in the Milita Immaculata The Medal itself does not possess any power, as it is a sacramental in the Catholic Church. This means that it is an extension of the seven sacraments and invokes the grace of God. As with any sacramental, miracles of conversion occur through God's providential plan, inspiring faith in Jesus Christ.

All credit goes back to God, who can use various material things to bring souls back to him.