48 As Our predecessor of immortal memory, Pius XII, has said—"The wonderful example of St. John Mary Vianney retains all of its force for our times." (62) For the lengthy prayer of a priest before the adorable Sacrament of the Altar has a dignity and an effectiveness that cannot be found elsewhere nor be replaced. And so when the priest adores Christ Our Lord and gives thanks to Him, or offers satisfaction for his own sins and those of others, or finally when he prays constantly that God keep special watch over the causes committed to his care, he is inflamed with a more ardent love for the Divine Redeemer to whom he has sworn allegiance and for those to whom he is devoting his pastoral care. And a devotion to the Eucharist that is ardent, constant and that carries over into works also has the effect of nourishing and fostering the inner perfection of his soul and assuring him, as he carries out his apostolic duties, of an abundance of the supernatural powers that the strongest workers for Christ must have.
Source: Sacerdotii Nostri Primordia (Vatican.va)