"Now We are well aware that the hope of salvation can never be absent wherever hearts are turned with sincere and ardent piety to the most holy Mother of God. Though attempts be made by men, no matter how powerful or impious, to extirpate the Christian religion and Christian virtue from the minds of the citizens, and though Satan himself may strive with every means to foster this sacrilegious struggle—as is described in the words of the Apostle of the Gentiles: 'For our wrestling is not against flesh and blood, but against the principalities and the powers, against the rulers of the world of this darkness, against the spirits of wickedness in the high places' (Eph 6:12)—yet notwithstanding, when Mary interposes her powerful protection, the gates of hell cannot prevail.
She, in fact, is the most loving and most powerful Mother of God and of us all, and never was it heard that anyone has had suppliant recourse to her and has not experienced her most efficacious protection. Continue, therefore, as you have been doing, to venerate her with fervent piety, and to love her ardently and to invoke her with these words which you have been accustomed to address to her: 'To you alone has it been given, O most holy and most pure Mother of God, unfailingly to have your petitions ever answered.'"
Pope Pius XII, Carissimis Russiae Populis , 1952.