5 In the second place, as every hope of safety lies in the protection and succour of our Heavenly Father in the midst of so great private and public necessities, We would earnestly desire to see confidence united with the revival of an assiduous zeal in prayer. In every great crisis of Christendom, and every time the Church was afflicted by evils within or dangers without, our fore fathers, with their eyes lifted to Heaven in supplication, taught us how and when we should seek for the light of our souls, for the strength of virtue, andfor help suited to the need. For deeply engraved upon men's minds were these precepts of Jesus Christ: "Ask and it shall be given you;"(2) "We ought always to pray and not to faint."(3) And with this teaching the word of the Apostle corresponds: "Pray without ceasing;"(4) "I desire, therefore, first of all that supplications, prayers, intercessions, and thanksgivings be made for all men."(5) Upon which subject St. John Chrysostom has left us this saying, not less true than ingenious, in the form of a comparison: "Even as man, who comes into the light of day naked and wanting all things, has been end owed by nature with hands to procure for himself all the necessaries of life; so in supernatural things, seeing that of himself he can do nothing, he has received from God the faculty of prayer, that he may use it wisely for the obtaining of all that is needful to his salvation."
Source: Quod Auctoritate (Vatican.va)