"Those of the Queen of cities (Constantinople) have attacked the synodic letter of the present very holy Pope, not in the case of all the chapters that he has written in it, but only in the case of two of them. One relates to the theology (of the Trinity) and, according to them, says: ‘The Holy Spirit also has his ekporeusis (ekporeuesthai) from the Son’. The other deals with the divine incarnation. "With regard to the first matter, they (the Romans) have produced unanimous evidence of the Latin Fathers, and also of Cyril of Alexandria, from the study he made of the gospel of St. John. On the basis of these texts, they have shown that they have not made the Son the cause (aitian) of the Spirit - they know in fact that the Father is the only cause of the Son and the Spirit, the one by begetting and the other by ekporeusis (procession) - but that they have manifested the procession through him (to dia autou proienai) and have thus shown the unity and identity of the essence… "They (the Romans) have therefore been accused of precisely those things which it would be wrong to accuse them, whereas the former (the Byzantines) have been accused of those things of which it has been quite correct to accuse them (Monothelitism). They have up till now produced no defence, although they have not yet rejected the things that they have themselves so wrongly introduced. “In accordance with your request, I have asked the Romans to translate what is peculiar to them [the ‘also from the son’] in such a way that any obscurities that may result from it will be avoided. But since the practice of writing and sending [the synodic letter] has been observed, I wonder whether they will possibly agree to do this. It is true, of course, that they cannot reproduce their idea in a language and in words that are foreign to them as they can in their mother-tongue, just as we too cannot. In any case, having been accused, they will certainly take some care about this.”
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