The sixth century was a time of still-existing imperial unity and complete unity of Universal Church. Pope Gregory the Great was worried that this unity could be broken by adoption of title oicoymenicόs in the Constantinople by Patriarch John IV Faster. In the West this title is translated with the term of universalis and in language differences it is understood that Constantinople patriarch wants to be the head of the Whole (Universal) Church. Pope Gregory begins to strongly protest and to demand that the patriarch reject the title oicoymenicόs as a profane addition. Theological problematization of the title was created in dispute between Old and New Rome. Pope considered that addition of title brings canonical problem and danger of schism. But he saw greatest danger in the Ecclesiological and Christological consequences. They implied that oicoymenicόs makes patriarch as the Head of Universal Church instead of Christ and makes dilaceration Corpus of the Lord. Through the mediation of the Eastern Patriarchs and clarification of the etymologically key pope preserves Ecclesial Unity.