13 The virtue of which we speak, like the others, is produced and nourished by divine faith; for God is the Author of all true blessings that are to be desired for themselves, as we owe to Him our knowledge of His infinite goodness, and our knowledge of the merits of our Redeemer. But, again, nothing is more fitted for the nourishment of divine faith than the pious habit of prayer, and the need of it at this time is seen by its weakness in most, and its absence in many men. For that virtue is especially the source whereby not only private lives may be amended, but also from which a final judgment may be looked for in those matters which in the daily conflict of men do not permit states to live in peace and security. If the multitude is frenzied with a thirst for excessive liberty, if the inhuman lust of the rich never is satisfied, and if to these be added those evils of the same kind to which We have referred fully above, it will be found that nothing can heal them more completely or fully than Christian faith.
Source: Exeunte Iam Anno (Vatican.va)