Second Council of Constantinople, Capitulum XIII

If anyone shall defend the impious writings of Theodoret, directed against the true faith and against the first holy Synod of Ephesus and against St. Cyril and his XII. Anathemas, and [defends] that which he has written in defence of the impious Theodore and Nestorius, and of others having the same opinions as the aforesaid Theodore and Nestorius, if anyone admits them or their impiety, or shall give the name of impious to the doctors of the Church who profess the hypostatic union of God the Word; and if anyone does not anathematize these impious writings and those who have held or who hold these sentiments, and all those who have written contrary to the true faith or against St. Cyril and his XII. Chapters, and who die in their impiety:  let him be anathema.

Translation: Henry R. Percival, The Seven Ecumenical Councils, NPNF II.14 (1900), via CCEL.