But the power of Mary over all the devils will especially shine forth in the latter times, when Satan will lay his snares against her heel: that is to say, her humble slaves and her poor children, whom she will raise up to make war against him. They shall be little and poor in the world’s esteem, and abased before all like the heel, trodden underfoot and persecuted as the heel is by the other members of the body. But in return for this they shall be rich in the grace of God, which Mary shall distribute to them abundantly. They shall be great and exalted before God in sanctity, superior to all other creatures by their lively zeal, and so well sustained with God’s assistance that, with the humility of their heel, in union with Mary, they shall crush the head of the devil and cause Jesus Christ to triumph.
--Saint Louis de Montfort, True Devotion to Mary