Pope Pius XII
Mystici Corporis Christi §39
Mystici Corporis Christi: On the Mystical Body of Christ
39 But our Divine Savior governs and guides the Society which He founded directly and personally also. For it is He who reigns within the minds and hearts of men, and bends and subjects their wills to His good pleasure, even when rebellious. "The heart of the King is in the hand of the Lord; whithersoever he will, he shall turn it." By this interior guidance He the "Shepherd and Bishop of our souls," not only watches over individuals but exercises His providence over the universal Church, whether by enlightening and giving courage to the Church's rulers for the loyal and effective performance of their respective duties, or by singling out form the body of the Church - especially when times are grave - men and women of conspicuous holiness, who may point the way for the rest of Christendom to the perfecting of His Mystical Body. Morever from Heaven Christ never ceases to look down with especial love on His spotless Spouse so sorely tried in her earthly exile; and when He sees her in danger, saves her from the tempestuous sea either Himself or through the ministry of His angels, or through her whom we invoke as Help of Christians, or through other heavenly advocates, and in calm and tranquil waters comforts her with the peace "which surpasseth all understanding."
Source: Mystici Corporis Christi (Vatican.va)