Nicene and Post-Nicene Fathers, Ser. II, Vol. XIV:
The Fourth Ecumenical Council.  The Council of Chalcedon.: Session V.

Session V.

(Labbe and Cossart, Concilia, Tom. IV., col. 555.)

Paschasinus and Lucentius the most reverend bishops and Boniface a presbyter, vicars of the Apostolic See of Rome, said:  If they do not agree to the letter of that apostolic and blessed man, Pope Leo, give directions that we be given our letters of dismission, and let a synod be held there [i.e. in the West].

[A long debate then followed as to whether the decree drawn up and presented should be accepted.  This seems to have been the mind of most of the bishops.  At last the commissioners proposed a committee of twenty-two to meet with them and report to the council, and the Emperor imposed this with the threat that otherwise they all should be sent home and a new council called in the West.  Even this did not make them yield (col. 560.)]

The most reverend bishops cried out:  Many years to the Emperor!  Either let the definition [i.e. the one presented at this session] stand or we go.  Many years to the Emperor!

Cecropius, the most reverend bishop of Sebastopol, said:  We ask that the definition be read again and that those who dissent from it, and will not sign, may go about their business; for we give our consent to these things which have been so beautifully drafted, and make no criticisms.

The most blessed bishops of Illyria said:  Let those who contradict be made manifest.  Those who contradict are Nestorians.  Those who contradict, let them go to Rome.

The most magnificent and most glorious judges said:  Dioscorus acknowledged that he accepted the expression “of two natures,” but not that there were two natures.  But the most holy archbishop Leo says that there are two natures in Christ unchangeably, inseparably, unconfusedly united in the one only-begotten Son our Saviour.  Which would you follow, the most holy Leo or Dioscorus?

The most reverend bishops cried out:  We believe as Leo.  Those who contradict are Eutychians.  Leo hath rightly expounded the faith.

The most magnificent and glorious judges said:  Add then to the definition, according to the judgment of our most holy father Leo, that there are two natures in Christ united unchangeably, inseparably, unconfusedly.

[The Committee then sat in the oratory of the most holy martyr Euphemis and afterwards reported a definition of faith which while teaching the same doctrine was not the Tome of Leo (col. 562).]