Commenting on the theology from the purported Marian apparitions at Medjugorje (unlike Fatima and others, this is, as of writing, not an approved apparition in Catholicism, but it is very popular and well-known, and, as the theology from the apparitions of Fatima, Our Lady of All Nations, etc., shows the spiritual dangers of Catholic Mariology):
She speaks words like these . . . ‘My Son Jesus Christ wishes to bestow special graces on you throw me . . .’ . . . ‘Pray and ask for the graces of God, I will pray that he gives them to you . . .’ (Michael O’Carroll, Medjugorje: Facts, Documents, Theology [Dublin: Veritas 1986], 184-5)
What does Medjugorje tell us about Our Lady?
First, that she cares immensely for those caught in the tragedy of our time. She has a mission from Almighty God to help suffering and threatened humanity. But with what devotion, delicacy, perseverance she fulfils it. She constantly appeals to men to allow her to help them. There is throughout the story and in the mentality of the children an astonishing certainty of Our Lady’s knowledge of all things, of her power in grasping a whole comprehensive plan and of entering into every detail which its accomplishment will entail . . . Mary is a person very conscious of the principal danger threatening those she loves: Satan . . . She follows his every move, knows his design, shows how to defeat him . . . Like her divine Son she chooses some for special favours, not because of who they are, but because of who she is . . . Mary, still a creature, but one in the confines of the deity. (Ibid., 187-88)
With respect to spiritually and prayer, the Mass and the Rosary are emphasised:
One form of prayer is preferred by Mary—that is as a personal form, of course she insists on the Mass, as we have seen, and urges that the Mass be prayed. But the Rosary has priority in the brie homiletic moments when she communicates with her children. So insistent is she on the great traditional prayer that she holds out the hope that if it were widely and fervently used, the troubles of the Church would wither away. (Ibid., 190)
To be fair, O’Carroll does admit what many Catholic scholars will readily admit, that the Marian dogmas evolved over time and are not to be found in the earliest strata of divine revelation:
The essential dogmas concerning Mary were thought out and formulated in the east, principally at Ephesus in 431 AD. The seeds of thought which would grow and flower in later dogmas, the Immaculate Conception, were sown then. (Ibid., 184)
Of course, this is problematic; for instance, Pius IX, when defining the Immaculate Conception in 1854, stated that the "doctrine always existed in the Church as a doctrine that has been received from our ancestors, and that has been stamped with the character of revealed doctrine."
For those wishing to delve deeply into Mariology, I would suggest my book:
Behold the Mother of My Lord: Towards a Mormon Mariology (2017). If one is Roman Catholic, I will happily send a PDF of the book for free (my email is IrishLDS87ATgmailDOTcom)