The book combines numerous citations in favor of devotion to the Blessed Virgin Mary from the Church Fathers and the Doctors of the Church with Saint Alphonsus' own personal views on Marian veneration and includes a number of Marian prayers and practices.
[1] The first part of the book focuses on the Salve Regina (Hail Holy Queen) and explains that God gave Mary to mankind as the "Gate of Heaven".
On this topic, St. Alphonsus quoted Saint Bonaventure, "No one can enter Heaven unless by Mary, as though through a door.
"[2] The second part of the book deals with the key Marian feasts such as the Immaculate Conception, Nativity, Purification, Annunciation, Assumption, etc.
[3] The third part focuses on the Seven Sorrows of Mary, explaining how her "prolonged martyrdom" was greater than that of all other martyrs.