Further the fathers of the Council of Chalcedon, by their practice, are authoritative exponents of the Canon of Ephesus. This is because they renewed the prohibition of the Council of Ephesus to “adduce any other faith,” but, in “the faith” which is not to be set aside, they included not only the Creeds of Nice and Constantinople, but the definitions at Ephesus and Chalcedon itself. The statements of the faith were expanded, because fresh contradictions of the faith had emerged. After directing that both Creeds should be read, the Council says,
Then, having in detail shewn how both heresies were confuted by it, and having set forth the true doctrine, they sum up:
The Council of Chalcedon enlarged greatly the terms although not the substance of the faith contained in the Nicene Creed; and that, in view of the heresies, which had since arisen; and yet renewed in terms the prohibition of the Canon of Ephesus and the penalties annexed to its infringement. It showed, then, in practice, that it did not hold the enlargement of the things proposed as de fide to be prohibited, but only the producing of things contradictory to the faith once delivered to the saints.
Its prohibition, moreover, to “hold” another faith shows the more that they meant only to prohibit any contradictory statement of faith. For if they had prohibited any additional statement not being a contradiction of its truth, then (as Cardinal Julian acutely argued in the Council of Florence), any one would fall under its anathema, who held (as all must) anything not expressed in set terms in the Nicene Creed; such as that God is eternal or incomprehensible
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