Just as God the Father delights in his creation of the woman who would be the mother of his Son, He bestows special privileges to her suitable for her role as Mediatrix of All Graces. As the Blessed Mother continues to bring Christ into the world by her prayers from Heaven, she is both an example and conduit of God's mercy. For a sinner that is in a state of spiritual misery, having pushed away baptism's supernatural graces, out of justice, does not deserve another chance for reconciliation. Yet, Our Lord still came to convert the sinner, and even the most hardened in habitual sin will benefit from Our Lady's intercessory prayers, Her requests, even on behalf of hardened sinners, are never refused by her Son. This is because not only is she always his mother, but he also sees the glory of the graces in her perfections and holiness.
It is also important to understand that she is given entirely to the Holy Will of God, as spouse of the Holy Ghost. Therefore, in the title of "Most Merciful", meaning, of all of God's creation, it is fitting that her perpetual virginity be extolled in the same breathe. Always a virgin, that is to also say, she is always given entirely to God, and after this, she gives herself to His Children, by bringing petitions on the behalf of those souls requesting her aide. We should, therefore, remember to invoke often our Lady under this title, Virgin Most Merciful.
Virgo clemens,
R. ora pro nobis.