If Providence bestows on the English Church only once in every half century a man like Bishop Westcott, this Church, I think, can be sure of a solid and sound longevity. Well, this Bishop Westcott spoke once enthusiastically of "_the noble catholicity which is the glory of the English Church_." My intention in this lecture is to describe to you an island in the Roman Catholic Church among the Slavs, which island is distinguished by a _noble catholicity_. "I believe in the holy _catholic_ apostolic church." This sentence that you repeat in London, as do the Roman Catholics in Rome, and we Orthodox in Moscow, has always two meanings, a sectarian and a universal, or a narrow one and a sublime one. The first meaning belongs to the people who imagine Christ standing at the boundary of their Church, turned with his face to them and with his back to all other "schismatic" peoples. The second belongs to the people who think that Christ may be also beyond their own churchyard; that the dwelling of their soul may be too narrow for His soul, and that their self-praisings and schismatic thunderings are very relative in His eyes. I propose to speak to-night about the people of this second category, _i.e._, of the people who are in the Christian history like a link connecting the different parts, the different Churches, into a higher unity. I will limit my considerations in this lecture to Slav Roman Catholicism. I call my theme of to-night "Slav Revolutionary Catholicism." Why "revolutionary"?