Cyril sends greeting in the Lord to the most religious and reverend fellow-minister Nestorius
I understand that there are some who are talking rashly of the reputation in which I hold your reverence, and that this is frequently the case when meetings of people in authority give them an opportunity. I think they hope in this way to delight your ears and so they spread abroad uncontrolled expressions. They are people who have suffered no wrong, but have been exposed by me for their own profit, one because he oppressed the blind and the poor, a second because he drew a sword on his mother, a third because he stole someone else's money in collusion with a maidservant and since then has lived with such a reputation as one would hardly wish for one's worst enemy. For the rest I do not intend to spend more words on this subject in order not to vaunt my own mediocrity above my teacher and master or above the fathers. For however one may try to live, it is impossible to escape the malice of evil people, whose mouths are full of cursing and bitterness and who will have to defend themselves before the judge of all.
But I turn to a subject more fitting to myself and remind you as a brother in Christ always to be very careful about what you say to the people in matters of teaching and of your thought on the faith. You should bear in mind that to scandalise even one of these little ones that believe in Christ lays you open to unendurable wrath. If the number of those who are distressed is very large, then surely we should use every skill and care to remove scandals and to expound the healthy word of faith to those who seek the truth. The most effective way to achieve this end will be zealously to occupy ourselves with the words of the holy fathers, to esteem their words, to examine our words to see if we are holding to their faith as it is written, to conform our thoughts to their correct and irreproachable teaching.
The holy and great synod, therefore, stated that
So we shall confess one Christ and one Lord. We do not adore the man along with the Word, so as to avoid any appearance of division by using the word "with". But we adore him as one and the same, because the body is not other than the Word, and takes its seat with him beside the Father, again not as though there were two sons seated together but only one, united with his own flesh. If, however, we reject the hypostatic union as being either impossible or too unlovely for the Word, we fall into the fallacy of speaking of two sons. We shall have to distinguish and speak both of the man as honoured with the title of son, and of the Word of God as by nature possessing the name and reality of sonship, each in his own way. We ought not, therefore, to split into two sons the one Lord Jesus Christ. Such a way of presenting a correct account of the faith will be quite unhelpful, even though some do speak of a union of persons. For scripture does not say that the Word united the person of a man to himself, but that he became flesh. The Word's becoming flesh means nothing else than that he partook of flesh and blood like us; he made our body his own, and came forth a man from woman without casting aside his deity, or his generation from God the Father, but rather in his assumption of flesh remaining what he was.
This is the account of the true faith everywhere professed. So shall we find that the holy fathers believed. So have they dared to call the holy virgin, mother of God, not as though the nature of the Word or his godhead received the origin of their being from the holy virgin, but because there was born from her his holy body rationally ensouled, with which the Word was hypostatically united and is said to have been begotten in the flesh. These things I write out of love in Christ exhorting you as a brother and calling upon you before Christ and the elect angels, to hold and teach these things with us, in order to preserve the peace of the churches and that the priests of God may remain in an unbroken bond of concord and love.