What is the New Rome? Canon 28 of Chalcedon

The other day, I shared a quotation from a saint recognized in the East, St. Maximos the Confessor (about 649 AD). It read, 

For the extremities of the earth and all in every part of it who purely and rightly confess the Lord, look directly towards the most holy Roman Church and its confession and faith, as it were to a sun of unfailing light, awaiting from it the bright radiance of the sacred dogmas of our fathers, according to what the six inspired and holy councils have purely and piously decreed, declaring most expressly the symbol of faith. For from the coming down of the incarnate Word among us, all the Churches in every part of the world have possessed that greatest Church along as their base and foundation, seeing that, according to the promise of Christ our Savior, the gates of hell do never prevail against it, that it possesses the keys of a right confession and faith in Him, that it opens the true and only religion to such as approach with piety, and shuts up and locks every heretical mouth that speaks injustice against the Most High (emphasis my own) 

My friend who is a catechumen for the (antiochian?) Orthodox Church asked, "Could he be talking about the New Rome and not the Old Rome?" Fair question. But first, what is meant by New Rome? For many Catholics, theologically speaking, there is just Rome, and that's it. Any mention about "New Rome" may sound foreign, and if they had to guess, they may think it refers to the Avignon Popes. But it does not. "New Rome" refers to Constantinople. I believe it comes from Canon 28 of the Council of Chalcedon. It reads,

Following in every way the decrees of the holy fathers and recognising the canon which has recently been read out–the canon of the 150 most devout bishops who assembled in the time of the great Theodosius of pious memory, then emperor, in imperial Constantinople, new Rome — we issue the same decree and resolution concerning the prerogatives of the most holy church of the same Constantinople, new Rome. The fathers rightly accorded prerogatives to the see of older Rome, since that is an imperial city; and moved by the same purpose the 150 most devout bishops apportioned equal prerogatives to the most holy see of new Rome, reasonably judging that the city which is honoured by the imperial power and senate and enjoying privileges equalling older imperial Rome, should also be elevated to her level in ecclesiastical affairs and take second place after her. The metropolitans of the dioceses of Pontus, Asia and Thrace, but only these, as well as the bishops of these dioceses who work among non-Greeks, are to be ordained by the aforesaid most holy see of the most holy church in Constantinople. That is, each metropolitan of the aforesaid dioceses along with the bishops of the province ordain the bishops of the province, as has been declared in the divine canons; but the metropolitans of the aforesaid dioceses, as has been said, are to be ordained by the archbishop of Constantinople, once agreement has been reached by vote in the usual way and has been reported to him. (emphasis my own)

So here we see Constantinople being called "new Rome". For what purpose? To give the church in Constantinople the same kind of power that the church in Rome had. For the Orthodox, this attempts to demonstrate a couple of things. It shows that whatever power Rome may have made a claim to in the past, it no longer resides with them, or that whatever power they had was only an accident of geography. Canon 28 states that Rome only had the power it had because it happened to be in an imperial city. So contrary to what us Catholics claim, there is no power inherit to the See of Peter/Rome, but only power which corresponds to local civic power. And according to Canon 28, since that power has shifted from Rome to Constantinople (this was written in 451 AD), Constantinople should now have that corresponding power and not Rome. Note the absence of theological justification for Old Rome having the power it had. The justification for transferring power is that power is grounded in local civic power. 

Now let us return to St. Maximos. St. Maximos was probably not talking about the Constantinople because he makes no mention of the local civic power and its connection to the Apostolic See. He is grounding the power of the Holy Roman Church in the "promise of Christ". He predicates all those promises, such as the gates of hell never prevailing against it, the keys, reveals true religion and has the power to put down heresies, to the Roman Church. This is essentially a theological justification for the power of Rome. But Canon 28, which is why some call Constantinople the New Rome, makes no such use of this theological justification. For this reason, St. Maximos is probably not talking about Constantinople. He is talking about Rome, the Apostolic See of St. Peter, having God given power. 

This quotation from an Eastern Saint may be troubling for an Eastern Orthodox who wishes to reject the authority/jurisdiction of the Roman See.