From the spiritual classic True Devotion to Mary:
Mary, being altogether transformed into God by grace and by the glory which transforms all the saints into Him, asks nothing, wishes nothing, does nothing contrary to the eternal and immutable will of God. When we read then in the writings of Sts. Bernard, Bernardine, Bonaventure and others that in Heaven and on earth everything, even God Himself, is subject to the Blessed Virgin, they mean that the authority which God has been well pleased to give her is so great that it seems as if she had the same power as God; and that her prayers and petitions are so powerful with God that they always pass for commandments with His Majesty, Who never resists the prayer of His dear Mother, because she is always humble and conformed to His Will.
— St. Louis de Montfort (1673-1716)