V. Theodoret's orthodoxy has been happily and thoroughly vindicated.
Wherefore this, too, it is our duty to provide against the Church's enemies, that, as far as in us lies, we leave them no occasion for slandering us, nor yet, in acting against the Nestorians or Eutychians, ever seem to have retreated before the other side, but that we shun and condemn both the enemies of Christ in equal measure, so that whenever the interests of the hearers in any way require it, we may with all promptitude and clearness strike down them and their doctrines with the anathema that they deserve, lest if we seem to do this doubtfully or tardily, we be thought to act against our will. And although the facts themselves are sufficient to remind your wisdom of this, yet now actual experience has brought the lesson home.
But blessed be our God, whose invincible Truth has shown you free from all taint of heresy in the judgment of the Apostolic See. To whom you will repay due thanks for all these labours, if you keep yourself such a defender of the universal Church as we have proved and do still prove you. For that God has dispelled all calumnious fallacies, we attribute to the blessed Peter's wondrous care of us all, for after sanctioning the judgment of his See in defining the Faith, he allowed no sinister imputation to rest on any of you, who have laboured with us for the Catholic Faith: because the Holy Spirit adjudged that no one could fail to come out conqueror of those whose Faith had now conquered.
Source: Letters (New Advent)