Schwerin, Philip, How the Bishop of Rome Assumed the Title of "Vicar of Christ"Archived 2017-08-05 at the Wayback Machine, p. 3, "Leo believed that in him was the voice of Peter. The Fourth Ecumenical Council at Chalcedon in 451 declared that Constantinople had the same patriarchal status as Rome (28th canon), a statement with which Leo never agreed, and which he even tried to declare invalid. When Leo tried to reinstate a defrocked French bishop, St. Hilary who presided over the Gallican Church as Supreme Pontiff, told Leo to keep his Roman nose out of French affairs. Leo's aspirations were strongly opposed, especially by the patriarch of Constantinople. Yet through him the papacy still gained some ground."
Schwerin, Philip, How the Bishop of Rome Assumed the Title of "Vicar of Christ"Archived 2017-08-05 at the Wayback Machine, p. 3, "Leo believed that in him was the voice of Peter. The Fourth Ecumenical Council at Chalcedon in 451 declared that Constantinople had the same patriarchal status as Rome (28th canon), a statement with which Leo never agreed, and which he even tried to declare invalid. When Leo tried to reinstate a defrocked French bishop, St. Hilary who presided over the Gallican Church as Supreme Pontiff, told Leo to keep his Roman nose out of French affairs. Leo's aspirations were strongly opposed, especially by the patriarch of Constantinople. Yet through him the papacy still gained some ground."
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