The translation of this fourteenth century prophecy was made by Helen Tzima Otto and appears in her book 'The Great Monarch' which contains english translations of several prophecies of the Byzantine apocalyptic tradition along with the greek version from which they were translated as contained in Migne's Patrologiae Graece. Her translations are accurate and plentiful in this particular book, but I should perhaps mention that she is herself Roman Catholic and includes a quite a lot of her own private interpretation in the notes which I have not reproduced here.
DISCOURSE OF A HOLY MAN ADDRESSED TO THE EMPEROR MANUEL II PALAEOLOGUS
(AD 1391 - 1425)
CONCERNING THE FALL OF CONSTANTINOPLE AND ITS SUBSEQUENT LIBERATION
When the Lord God gives His consent, the Ishmaelites will lay siege upon Constantinople and many islands and lands will fall prostrate before Ishmael. After the City has been conquered, and after an elapse of ten years, two months, and additionally of three hundred ninety years of control by the Ishmaelites, namely, almost till the fourth century since its fall, it will befall upon the Christians to create a great naval force. And the members of the clergy and the monastics as well as every social stratum of humanity, against their own will, but led by a divine sign will come to Constantinople and only a few chosen ones will be left behind, here and there; this naval force will become so great that counting only the heads and leaders of the navy it shall reach the figure of seventy thousand officers. And each one of them will have under his command ten thousand men.
The ships will be put into the sea, and they will depart for Constantinople and to the place called Kontoscalian. Ishmael having seen how great a force is gathered in the City will abandon Constantinople, and will flee to safety in Asia.
And the various leaders of the Christian armies will begin fighting among themselves to determine who will be the one to rule Constantinople; and they will draw their swords and attempt to cut each other into many pieces, and so much slaughter will take place that all depressions on the surface of the land of the City and all its soil will be drenched in blood to such a depth so that a three year old calf could be drowned in it, and the blood will flow to the sea up to eighteen stadia distance and this slaughter is destined to be so tremendous that all sinners will die in its course and none among them will survive.
Then an Angel of the Lord will descend from Heaven upon a gesture from God, and the Angel will have in His hands the sceptre and sword of the most Saintly Emperor Constantine, and he will crown the Emperor of Peace. This King will be present in Constantinople, and will be a participant in the middle of those present in the war; and the Angel will offer to him the sceptre and the sword, and he will call him the "Charitable One." And he will say to him "Be courageous and strong and be victorious over the enemies of Christ and of His Holy Apostles, and immediately that quarrel and that war will cease; and three angels will fetch the king and having carried him to the Great Church of the Holy Wisdom of God, they will crown him Emperor.
All those people who will have survived the war will also be just persons in the future, because the fighting against each other will not cease until all sinners have perished. And there in the new Zion, namely, the Church of the Holy Wisdom of God, the people will gather in order to pay homage to this good Emperor; and the people will arrive coming from all over the World, every human will come to render him homage.
Seeing them coming from afar, the Emperor will rise to go greet them, and he will receive them with great joy; and they will inquire where he has come from, and the King will tell them. Then he will offer a large sum of money to all those who come to the City of Constantinople, and they will enquire "What is all this money for?" And he will respond to them "That much and even more than this is for you and all those who will come to the City to settle; I will provide such person with houses and lands and everything else he desires. And I will be like one of your brothers to you, and we will all be brothers, and Father to us all is the Lord Jesus Christ." Thus, for the duration of seven years people will be gathering in Constantinople, and all the islands will become depopulated by virtue of this resettlement. And within these seven years, all of Constantinople will be replenished with Christian people along with their wives and children.
Then the Emperor will say to them: "Fathers and brothers, it is good to make an expedition against our enemies, in order to erect the Cross and to avenge the blood of our people. Then everyone with one voice will tell him "Let thy will be done, oh Despota, because it was the voice of God that spake through thy mouth. So, let it be done according to thy order." Then the Emperor will rise and all the people at his side, and they will campaign against the Ishmaelites. Then the saying will come to pass which says "One will chase one thousand and two will force to flight myriads," and this driving out will continue till they reach the Beautiful Gates which the Emperor Alexandre of Macedonia closed in his day. And they will force the enemy to move beyond that spot, and then the Emperor will say that the Ishmaelites will not be able to raise their head from now on, and not only the Turks, proper, but also the Saracens and the Scythians and every other nation that does not believe in Christ.
Then the Emperor will take the road of return to Constantinople, and having entered the City, the treasures of the Earth will be revealed, and wherever there is gold or silver to be found, there the earth will emit smoke. And the charitable Emperor will say "Enter and see what is this smoke." And upon the command of the noble Emperor, they will enter and discover treasures of gold and silver, and all this will be offered as a gift to the pious ones. Later, many more and even more valuable treasures will be discovered, and the Emperor will do with those treasures likewise. Such will be the plethora of the treasure that a portion thereof will be cast down on the ground as superfluous because they will be unable to identify any more uses for it.
And rejoicing and exultation will prevail all over the world, and there will be nobody who is perpetrating injustice or is a victim thereof, considering that all sinners will already have been wiped out from the Earth. And the Earth will give its fruit a bounty crop, a hundredfold, and according to the common saying honey and milk will flow from the land.
The Emperor will spend three years waging wars against the infidel nations. Afterwards, he will return to the Queen of Cities, and there he will rest in joy and delight for the duration of twenty years; and afterwards his own son will reign in great joy and delight for thirty years. Afterwards, another one from the Emperor's line will reign, a man of great cruelty and hatred of man, and his reign will be two months long. Then Enoch and Elijah and Saint John the Evangelist will come to preach to all the Christians that a certain deceiver is on his way. Take heed not to be led astray as the Holy Gospel already makes manifest.