by St. Alphonsus Liguori, Doctor of the Church and Founder of the Congregation of the Holy Redeemer
Final perseverance, the grace for us to die in the love and friendship of Our Lord, is so great a gift of God, that (as it was declared by the Holy Church through the Council of Trent) it is quite gratuitous on His part, and we cannot merit it. Yet we are told by St. Augustine, that all who seek for it obtain from God; and... they obtain it infallibly, if only they are diligent in asking for it to the end of their lives. For as St. Robert Bellarmine [a Doctor of the Church] remarks, "that which is daily required must be asked for every day." Now if it is true that all the graces that God dispenses to men pass through the hands of Mary, it will be equally true that it is only through Mary that we can hope for this greatest of all graces - perseverance. And we shall obtain it most certainly, if we always seek it with confidence through Mary. This grace She Herself promises to all who serve Her faithfully during life, in the following words of Sacred Scriptures and which are applied to Her by the Church - the ground and pillar of the truth (1 Tim. 3.15) - on the Feast of the Immaculate Conception: They that work by me shall not sin. They that explain me shall have life everlasting (Ecclus [Ecclesiasticus, the Catholic Douay-Rheims Version] 24.30).
In order that we may be preserved in the life of grace, we require spiritual fortitude to resist the many enemies of our salvation. Now this fortitude can can be obtained only by means of Mary, and we are assured of it in the Book of Proverbs, for the Church applies this passage to the Blessed Virgin: Strength is mine; by me kings reign (8.14); meaning, by the words strength is mine, that God has bestowed this precious gift on Mary, in order that She may dispense it to Her faithful clients. And by the words, by me kings reign, She signifies that by Her means Her servants reign over and command their senses and passions, and thus become worthy to reign eternally in heaven. Mary is that tower spoken of in the Book of Canticle of Canticles: Thy neck is as the tower of David, which is built with bulwarks; a thousand bucklers hang upon it, all the armor of valiant men (4.4). She is as a well-defended fortress in defence of Her lovers, who in their wars have recourse to Her. In Her do Her clients find all shields and arms, to defend themselves against hell.
And for the same reason the Most Blessed Virgin is called a plane-tree in the words of Ecclesiasticus: As a plane-tree by the water in the streets was I exalted (24.19). The plane-tree has leaves like shields, to show how Mary defends all who take refuge with Her. This Holy Virgin is also called a plane-tree because as the plane-tree shelters travellers under its branches from the heat of the sun and from the rain, so do men find refuge under the mantle of Mary from the ardor of their passions and from the fury of temptations. Truly are those souls to be pitied who abandon this defence, in ceasing their devotion to Mary, and no longer recommending themselves to Her in the time of danger. If the sun ceased to rise, says St. Bernard, how could the world become become other than a chaos of darkness and horror? And applying his question to Mary, he repeats it. "Take away the sun, and where will be the day? Take away Mary, and what will be left but the darkest night?" When a soul loses devotion to Mary, it is immediately enveloped in darkness, and in that darkness of which the Holy Ghost speaks in the Psalms: Thou hast appointed darkness, and it is night; in it shall all the beasts of the woods go about (103.20, chapter and verse after the Sacred Latin Vulgate Bible). When the light of heaven ceases to shine in a soul, all is darkness, and it becomes the haunt of devils and of every sin. St. Anselm says, that "if anyone is disregarded and condemned by Mary, he is necessarily lost," and therefore we may with reason exclaim, "Woe to those who are in opposition to this sun?" Woe to those who despise its light! that is to say, all who despise devotion to Mary. St. Germanus: "As breathing is not only a sign but even a cause of life, so the name of Mary, which is constantly found on the lips of God's servants, both proves that they are truly alive, and at the same time causes and preserves their life, and gives them every succor."
Mary says in the following words of the Book of Proverbs applied to Her by the Holy Church: Blessed is the man that heareth me, and that watcheth daily at my gates, and waiteth at the posts of my doors (8.34) - as if She would say, Blessed is he that hears my voice and is constantly attentive to apply at the door of my mercy, and seeks light and help from me. For clients who do this, Mary does Her part, and obtains them the light and strength they require to abandon sin and walk in the paths of virtue. For this reason, Pope Innocent III, beautifully calls Her "the moon at night, the dawn at break of day, and the sun at midday." She is a moon to enlighten those who blindly wander in the night of sin, and makes them see and understand the miserable state of damnation in which they are; She is the dawn (that is, the forerunner of the sun) to those whom She has already enlightened, and makes them abandon sin and return to God Who Is the true Sun of Justice; finally, She is a sin to those who are in a state of grace, and prevents them from falling again into the precipice of sin.
Learned writers apply the following words of Ecclesiasticus to Mary: Her bands are a healthful binding (6.31). "Why bands?" asks St. Laurence Justinian, "except it be that She binds Her servants, and thus prevents them from straying into the paths of vice." And truly this is the reason for which Mary binds Her servants. St. Bonaventure also, in his commentary on the words of Ecclesiasticus, frequently used in the "Officium Parvum" or the "Little Office of the Blessed Virgin Mary", My abode is in the full assembly of saints (24.16), says the Mary not only has Her abode in the full assembly of saints, but also preserves them from falling, keeps a constant watch over their virtue, that it may not fail, and restrains the evil spirits from injuring them. Not only has She Her abode in the full assembly of the saints, but She keeps the saints there, by preserving their merits that they may not lose them, by restraining the devils from injuring them, and by withholding the arm of Her Son from falling on sinners.