Were it otherwise, had he not confidence in the darkest day, and the most hostile district, he would be relinquishing a principal note, as it is called, of the Church. She is Catholic, because she brings a universal remedy for a universal disease. The disease is sin; all men have sinned; all men need a recovery in Christ; to all must that recovery be preached and dispensed. If then there be a preacher and dispenser of recovery, sent from God, that messenger must speak, not to one, but to all; he must be suited to all, he must have a mission to the whole race of Adam, and be cognisable by every individual of it. I do not mean that he must persuade all, and prevail with all-for that depends upon the will of each; but he must show his capabilities for converting all by actually converting some of every time, and every place, and every rank, and every age of life, and every character of mind. If sin is a partial evil, let its remedy be partial; but, if it be not local, not occasional, but universal, such must be the remedy. A local religion is not from God. The true religion must indeed begin, and may linger, in one place; nay, for centuries remain there, provided it is expanding and maturing in its internal character, and professes the while that it is not yet perfect. There may be deep reasons in God’s counsels, why the proper revelation of His will to man should have been slowly elaborated and gradually completed in the elementary form of Judaism; but that Revelation was ever in progress in the Jewish period, and pointed by its prophets to a day when it should be spread over the whole earth. Judaism then was local because it was imperfect; when it reached perfection within, it became universal without, and took the name of Catholic.
J. H. Newman, Discourses Addresssed to Mixed Congregations, (Discourse XII Prospects of the Catholic Missioner), Gracewing-University of Notre Dame Press, Birmingham Millennium Oratory Edition 2001, Vol VI, p 246,