St. Louis Marie de Montfort is best known for his promotion of a particular form of devotion to the Blessed Virgin Mary, known variously as "The Holy Slavery of Jesus in Mary", "Total Consecration to Jesus through Mary", or simply "True Devotion to Mary" (from the title of his best-known book, "Treatise on True Devotion to the Blessed Virgin Mary").

However, just as it is a mistake to suppose that the Roman Catholic Church places devotion to Mary above commitment to Christ, so it is equally mistaken to think that St. Louis Marie's spirituality is exclusively, or above all, "Marian" (concerned with Mary, the Mother of Jesus). As he says himself (in "Treatise on True devotion to the Blessed Virgin Mary", no. 61):

Jesus, our Saviour, true God and true man must be the ultimate end of all our other devotions; otherwise they would be false and misleading;

If then we are establishing sound devotion to our Blessed Lady, it is only in order to establish devotion to our Lord more perfectly, by providing a smooth but certain way of reaching Jesus Christ. If devotion to our Lady distracted us from our Lord, we would have to reject it as an illusion of the devil.

This is stated even more clearly in "The Love of Eternal Wisdom", one of the earliest of St. Louis Marie's writings, in which his concern for devotion to Mary is placed clearly in the context of his prime concern, which is relationship to Jesus Christ, whom he sees as the personification of "the Eternal and Incarnate Wisdom of God". It is only at the end of this book that he describes the four principal means of arriving at a knowledge and love of Jesus, "Eternal Wisdom":

1. Ardent desire
2. Constant prayer
3. "Universal" mortification
4. Genuine devotion to Mary

The greatest means of all, and the most wonderful of all secrets for obtaining and preserving divine Wisdom is a loving and genuine devotion to the Blessed Virgin.