Pope Gregory the Great, Emperor Trajan and praying for the damned

This article discusses the legend that Pope Gregory prayed for the salvation of the damned soul of the long dead Emperor Trajan--resulting in the Emperor's salvation. The legend, which seems almost certainly apocryphal, has had a big impact in the Orthodox Church's doctrines and practices concerning the dead and Hell. This implication seem to justify practices like rejecting private revelation as basis for doctrine, and making such things only private devotions, and would seem to be another reason the Second Vatican Council's efforts to remove legends (especially ones for the basis for certain saints) from the Roman Calendar was justified (though Gregory the Great is recognized as a saint without respect to this story).

In the Middle Ages a story floated around that Pope Gregory the Great (died March 12, AD 604) when thinking about the pagan Emperor Trajan was so moved by his justice and morality that cried for the Emperor and he was released from Hell or got a mitigated damnation, some say the Emperor resurrected, accepted the faith, then died again and went to heaven. The earliest, most well-known accounts (Whitby, Pseudo-Paul the Deacon, Pseudo-Damascene) has God telling the Pope to not make this request for a pagan/impious ever again.

However, Eastern Orthodox apologists and some theologians appeal to this story (in addition to the Nestorian bishop "St" Isaac the Syrian's comments on Hell, despite his comments being based on the writings of the anathematized Theodore of Mopsuestia) as evidence the doctrine of universal reconciliation was not totally condemned at the time of Justinian in the synod of Constantinople 543, or that at least some of those that are damned, having died in mortal sin, can be saved after death by prayers, though the story says not to do this.

The earliest written account attributed to an anonymous monk from the Whitby Abbey in England several generations later reads:

"Some of our people also tell a story related by the Romans of how the soul of the Emperor Trajan was refreshed and even baptized by St. Gregory's tears, a story marvelous to tell and marvelous to hear. Let no one be surprised that we say he was baptized, for without baptism none will ever see God; and a third kind of baptism is by tears. One day as he was crossing the Forum, a magnificent piece of work for which Trajan is said to have been responsible, he found on examining it carefully that Trajan, though a pagan, had done a deed so charitable that it seemed more likely to have been the deed of a Christian than a pagan. For it is related that, as he was leading his army in great haste against the enemy, he was moved to pity by the words of a widow, and the emperor of the whole world came to a halt. She said, 'Lord Trajan, here are the men who killed my son and are unwilling to pay me recompense.' He answered, 'Tell me about it when I return. and I will make them recompense you.' But she replied, 'Lord, if you never return, there will be no-one to help me.' Then, armed as he was, he made the defendants pay forthwith the compensation they owed her, in his presence. When Gregory discovered this story, he recognized that this was just what we read about in the Bible, 'judge the fatherless, plead for the widow. Come now and let us reason together, saith the Lord.' Since Gregory did not know what to do to comfort the soul of this man who brought the words of Christ to his mind, he went to St Peter's Church and wept floods of tears, as was his custom, until he gained at last by divine revelation the assurance this his prayers were answered, seeing that he had never presumed to ask this for any other pagan.--The Earliest Life of Gregory the Great, Chapter 29. page 127. Written by an Anonymous Whitby monk c. AD 680-704. Translated by Bertram Colgrave. 1985.

This, the oldest version of the account extant, is largely unknown to modern audiences Orthodox or Catholic. Notice this account points to the virtues of Emperor Trajan and seems ignorant of his atrocities in killing Christians. A commentary suggests the story of the widow demanding recompense is out of place:

""Her son, she says, has been murdered; she has the perpetrators in hand; but they refuse to pay the recompense: we are in the realm of the Germanic wergeld."--The Unbounded Community: Papers in Christian Ecumenism in Honor of Jaroslav Pelikan The Virtuous Pagan, Page 47 

 A version of the story was retold by John the Deacon in a biography about Pope Gregory the Great commissioned by Pope John VIII in the ninth century is as follows (unfortunately I cannot find a translation):

It's read also in the hands of the same English Churches, that Gregory going forth through Trajan's forum, at one time he made beautiful with the most beautiful buildings, his judgement where a widow had been comforted is to be remembered and wondered: what is certainly just as previously received, so he himself had.  At a certain time, Trajan was in a great haste to prepare for an impending war, a certain widow approached [him] mournfully saying: My innocent son, you reign, he is destroyed; I beseech that, because he is to pay me you are not able, his blood legally fit to be avenged.   And Trajan, if he returns safe from battle, will himself use his legal authority for everything in the response. The widow said: If you die in battle, who will give it to me?  Trajan said: He who will rule after me.  The widow said: And what does it profit you if another renders me justice?  Trajan answered: Certainly, nothing.  And the widow: Is it not better for you that you render me justice, and in exchange for that you receive a fee, rather than assign it to another? Then Trajan, moved at the same time by reason and by pity, got down from the horse and did not depart before himself having concluded the trial on the side of the widow. Therefore this kind judgement, they assert Gregory remembered arriving to St Peter the Apostle's basilica; and there so long concerning a wondering as most merciful leader lamenting, till when he encountered a response the following night, for Trajan was heard, tantum for no other pagan offer prayer.  But with concern to the supreme miracle of the Romans which nobody doubts, concerning this it is read among the Saxons, this petition freed Trajan's soul from the torment of hell, for which also is to be seen with very much doubt, which such a size of a doctor in no wise certainly presumes to pray for a pagan; which his fourth book of Dialogues teaches the same is the reason why saints should not pray in future judgement for sinners are condemned to eternal fire; Nor do saintly men on earth pray for deceased infidels and godless people. not considering that it is not read Gregory prayed for Trajan, but only he wept.  For thus with no praying Gregory, wailing could be heard, as Moses with suffering quietly, he could be seen crying, the Lord said to his silent lips: "Why do you cry to me?" (Exodus 14:15).  Without a doubt Almighty God searches unraveling hearts, and often He gives pity, which men although as the flesh desires, but yet do not presume to ask.  Hence the Psalmist: "The Lord has heard the desire of the poor, and the desires of their heart you have heard" (Psalm 9:38).   And it should be noted that it is not read Gregory offered prayers for Trajan's soul to be freed from hell, and placed in paradise, which is completely not credible discern according to that which is written, "unless m a man be born again of water and the Holy Spirit, he shall not enter the Kingdom of Heaven (John 3:5);" but simply said, freed only from the torment of hell (inferno). Which is to say, it could be seen credibly, seeing as in this manner the soul in Hell were availed, and through the mercy of God, Hell's torment is not felt, as a single Gehenna's fire prevails equally detaining all sinners, thus through God's justice all are not able in a like manner burned. But as far as each one deserves blame, God's just judgement only he will feel and punishment.--John the Deacon , S. Gregorii Papae Vita (Life of Pope St Gregory) II.44 Patrologia Latina (Migne): Volume 75, 105-106 (written between AD 872-882) (in process of translating--I am not fluent by any stretch)

Legitur etiam penes easdem Anglorum Ecclesias, quod Gregorius per forum Traiani, quod ipse quondam pulcherrimis aedificiis venustarat, procedens, iudicii eius quo viduam consolatus fuerat recordatus atque miratus sit: quod scilicet sicut a prioribus traditur, ita se habet.  Quodam tempore, Traiano ad imminentis belli procinctum festinanti vehementissime, vidua quaedam processit flebiliter dicens: Filius meus innocens, te regnante, peremptus est; obsecro ut, quia eum mihi reddere non vales, sanguinem eius legaliter vindicare digneris.   Cumque Traianus, si sanus reverteretur a praelio, hunc se vindicaturum per omnia responderet, vidua dixit: Si tu in praelio mortuus fueris, quis mihi praestabit?  Traianus dixit: Ille qui post me imperabit.  Vidua dixit: Et tibi quid proderit, si alter mihi iustitiam fecerit?  Traianus respondit: Utique nihil.  Et vidua: Nonne, inquit, melius tibi est ut tu mihi iustitiam facias, et tu pro hoc mercedem tuam recipias, quam alteri hanc transmittas? Tunc Traianus ratione pariter pietateque commotus, equo descendit, nec ante discessit quam iudicium viduae per semet imminens profligaret. Huius ergo mansuetudinem iudicis asserunt Gregorium recordatum ad sancti Petri apostoli basilicam pervenisse; ibique tandiu super errore tam clementissimi principis deflevisse, quousque responsum sequenti nocte cepisset, se pro Traiano fuisse auditum, tantum pro nullo ulterius pagano preces effunderet.  Sed cum de superioribus miraculis Romanorum sit nemo qui dubitet, de hoc quod apud Saxones legitur, huius precibus Traiani animam ab inferni cruciatibus liberatam, ob id vel maxime dubitari videtur, quod tantus doctor nequaquam praesumeret pro pagano prorsus orare; qui quarto Dialogorum suorum libro docuerit eamdem causam esse cur non oretur a sanctis in futuro iudicio pro peccatoribus aeterno igne damnatis; quae nunc etiam causa est ut non orent sancti homines pro hominibus infidelibus impiisque defunctis; non advertentes quia non legitur pro Traiano Gregorium exorasse, sed tantum flevisse.  Sic enim cum non oraverit Gregorius, plangendo potuit exaudiri, sicuti Moyses cum dolendo taceret, potuit clamasse videri, cui Dominus tacenti labiis: Quid clamas, inquit, ad me (Exod. XIV, 15)?  Nimirum Deus omnipotens corda renesque scrutatur, et frequenter ea misertus concedit, quae homo quamvis ut carnalis desideret, tamen petere non praesumit.  Unde Psalmista: Desiderium pauperum exaudivit Dominus, et desideria cordis eorum audivit auris tua (Psal. XIX, 17).   Et notandum quia non legitur Gregorii precibus Traiani anima ab inferno liberata, et in paradiso reposita, quod omnino incredibile videtur propter illud quod scriptum est: Nisi quis renatus fuerit ex aqua et Spiritu sancto non intrabit in regnum coelorum (Ioan. III, 3); sed simpliciter dicitur, ab inferni solummodo cruciatibus liberata. Quod videlicet potest videri credibile quippe cum ita valeat anima in inferno existere, et inferni cruciatus per Dei misericordiam non sentire, sicuti unus gehennae ignis valet omnes peccatores pariter detinere, sic per Dei iustitiam cunctos non valet aequaliter exurere. Nam uniuscuiusque quantum meruit culpa, iusto Dei iudicio tantum sentietur et poena.--John the Deacon , S. Gregorii Papae Vita (Life of Pope St Gregory) II.44 Patrologia Latina (Migne): Volume 75, 105-106 (written between AD 872-882)

What is clear from John the Deacon is that he cites the fourth book of the Dialogues by Pope Gregory where he says the damned in Gehenna are not to be prayed for--he quotes it as I do later in this article. John the Deacon certainly doesn't believe the Pope prayed for the Emperor.

The story as attributed to Paul the Deacon has been determined to have not but written by him but about 50 years later it was inserted into his text on Gregory the Great, this portion of text is sometimes called "pseudo-Paul":.

"The first edition of this work (Paul the Deacon's vita of Gregory) was published in 1887 and it says nothing about Trajan. The vita of Gregory ascribed to Paul in both the Acta Sanctorum and Migne's Patrologia latina is a pseudonymous and interpolated version written a century later which draws on the intervening vita of Gregory by John the Deacon..."--The Unbounded Community: Papers in Christian Ecumenism in Honor of Jaroslav Pelikan The Virtuous Pagan, Page 47

The interpolated text is translated as follows:

"Also, this same priest, who was very fervent and acceptable to God, on a certain day proceeded through the forum of Trajan, which he knew had been built in an extraordinary manner. And he viewed the monuments of Trajan's clemency, especially that memorable one which commemorates the fact that when this earthly prince surrounded by a group of soldiers once was going on an expedition he had met a very old widow. She was worn out with old age as well as with sorrow and poverty, and he was stopped by her tears and wails. "O most loyal Prince Trajan, behold here are men who have killed my only son, my support and my only comfort. And, wishing to kill me along with him, they refused to pay me any restitution for him." Being in a hurry, he said to her as he passed on, "When I return, tell me this, and I shall render you full justice." Then she said, "Master, and if you do not return, what shall I do?" He listened to this plea and ordered the accused to be brought before him.  Nor, when it was suggested by everyone that he hastened the business, did he move a step from the place until he had arranged that the widow be paid from his purse whatever was decreed by law. And, at length, by prayers and tears of supplication, sorrowing over his misdeeds and moved by inward mercy, he freed the accused from their praetorial bonds not much by his power as by his devotion and leniency. Then the venerable pontiff, moved by grace, began with tearful sighs and supplicant words to quote these prophecies and evangelical maxims; "Thou, O Lord. hast said: 'Judge for the fatherless, defend the widow; and come, and accuse me.' And elsewhere, 'Forgive, and it shall be forgiven you;' be no unmindful, I beseech Thee, that I a most unworthy sinner, on account of the glory of Thy name and on Thy most faithful promise in the case of this devoted man do humbly implore Thy clemency."  And arriving at the tomb of Saint Peter, he prayed there for a long time and wept and was, as it were, overcome by sleep and rapt in ecstacy in which he learned through a revelation that he had been graciously heard. And lest in the future he should presume to seek favors for anyone who had died without holy baptism he was deservedly reproved. In this connection he was allowed to be asked certain things by inquisitive people of imperfect faith and more things by those who believe the truth when it is spoken faithfully. And he was allowed to explain that the things which are or seem impossible to men are easy to God. In this act of divine goodness and power, nevertheless, it seemed desirable that his opinion be honored and disputed by no one."--Pseudo-Paul the Deacon (c 810-840) interpolated in "The Life of Saint Gregory the Great" by Paul the Deacon,c. AD 770-780 translation by SISTER MARY EMMANUEL JONES, R.S.M,

Idem vero perfectissimus et acceptabilis Deo sacerdos, cum quadam die per forum Trajani, quod opere mirifico constat esse exstructum, procederet, et insignia misericordiae ejus conspiceret, inter quae memorabile illud comperiret, videlicet quod cum idem orbis princeps in expeditionem, circumvallatus militum cuneis, pergeret, ibidem obviam habuerit vetustissimam viduam, senio simulque dolore ac paupertate confectam, cujus lacrymis atque vocibus sic compellatur: Princeps piissime Trajane, ecce hic sunt homines qui modo mihi unicum filium, senectutis scilicet meae baculum et omne solatium, occiderunt; meque una cum eo volentes occidere, dedignantur etiam mihi pro eo rationem aliquam reddere. Cui ille festinato, ut res exigebat, pertransiens: Cum rediero, inquit, dicito mihi, et faciam tibi omnem justitiam. Tum illa: Domine, inquit, et si tu non redieris, ego quid faciam? Ad quam vocem substitit, et reos coram se adduci fecit. Neque, cum suggereretur a cunctis accelerare negotium, gressum a loco movit, quousque et viduae a fisco, quod juridicis sanctionibus decretum est, persolvi pro re fecit; demumque supplicationum precibus et fletibus super factis suis poenitentes viscerali clementia flexus, non tam potestate quam precatu et lenitate vinctos, praetorialibus catenis absolvit. Hujus rei gratia compunctus venerabilis pontifex, coepit lacrymosis gemitibus secum inter verba precantia, haec siquidem prophetica et Evangelica revolvere oracula: Tu, Domine, dixisti: Judicate pupillo, defendite viduam; et venite, et arguite me (Isa. I, 17). Et alibi: Dimittite, et dimittetur vobis; ne immemor sis, quaeso, peccator ego indignissimus, propter nomen gloriae tuae, et fidelissimae promissionis tuae, in hujus devotissimi viri facto, pietati tuae humiliter supplico (Marc. VI, 27). Perveniensque ad sepulcrum beati Petri, ibi diutius oravit, et flevit, atque veluti somno correptus in exstasim est raptus, quo se per revelationem exauditum discit; et ne ulterius jam talia de quoquam sine baptismate sacro defuncto praesumeret petere, promeruit castigari. Qua in re, licet a minus perfectae fidei et curiosis quaedam valeant quaeri, et plura ab his qui credunt veritati fideliter dicenti, quae apud homines impossibilia sunt vel videntur, facilia sunt apud Dominum, salubriter explanari, tutius tamen videtur in hoc actu divinae pietatis et potestatis judicium venerari, et a nemine discuti--Pseudo Paul the Deacon, Vita S. Gregorii Magni, Section 27

The most known version of the story is found in pseudo-Damascene, a work previously attributed to St John of Damascus, it goes as follows:

"...Gregory the Dialogist, the senior bishop of Rome, as everybody knows, was a man well known for his righteousness and knowledge. They even say that the divine angel assisted him when he was conducting the liturgy. One day this Gregory, while taking a walk among the stones, stood carefully still and uttered a mighty prayer directed toward the soul-loving Lord for the forgiveness of the sins of Trajan the king. Immediately after saying these things he heard a voice borne to him from God: "I have heard your prayer, and I grant forgiveness to Trajan. But you (singular) should not again put forward prayers addressed to me on behalf of pagans (ασεβων)." And that this story is true and blameless, the whole East and West is witness. Look, this even surpasses what happened to Falconilla. For she was a party to no other evil (beyond idolatry), but Trajan brought about the deaths of many martyrs. You are marvelous, Lord, and marvelous are your works. We praise your incredible goodness of heart, because you always incline toward the love of human beings."--Pseudo-Damascene, "Homily for Meat-Fare Saturday" PGM 95. 261-64 Translated by Jeffrey A. Trumbower in Rescue for the Dead: The Posthumous Salvation of Non-Christians in Early Christianity. Page 145.

Eventually, this story has largely been forgotten in the West. It is mentioned by Dante and St Thomas Aquinas and several other writings up until around the Renaissance, but largely doubted or rejected as absurd by then. The story was discounted by John the Deacon.

It must be noted the story is of similar nature and absurdity to the Seven Sleepers of Ephesus (which was a popular Christian legend that the Quran took up as true), and the legend of St Brenan the Navigator where he tells of Judas being placed on a rock in the Atlantic Ocean as a temporary reprieve from Hell on holy days (only to be thrown back in the rest of the year!).

First and most importantly, it must be noted that Pope Gregory the Great (St Gregory the Dialogist as he is called in the East) explicitly rejected praying for the damned.

The saints in heaven, therefore, do not offer prayers for the damned in hell for the same reason that we do not pray for the Devil and his angels. Nor do saintly men on earth pray for deceased infidels and godless people. And why? Because they do not wish to waste their prayers in the sight of a just God by offering them for souls who are known to be condemned. But if the saints, while still alive and conscious of their own failings, have no compassion on the unjust sinners in hell, if they show no compassion whatever at a time when they realize that their own sins and imperfections are worthy of God's punishment, how much more severely will they look upon the torments of the damned once they are freed from sin and corruption and stand near to their eternal Judge, closely united with Him? In their intimate association with the most just of all judges, the force of His severity will penetrate their minds, and they will be utterly displeased with anything that is out of harmony with the least detail of the eternal law. --Pope Gregory the Great, Dialogue IV, 44 (taken from The Fathers of the Church, Volume 39, translated by Odo John Zimmerman, O.S,B. book four, page 257)

Commenting on this same passage one translator notes:

CHAPTER XLIV. p. 240. This doctrine of St. Gregory's, that the faithful do not pray for the souls of those whom they suppose to be in Hell, is more explicitly stated in the Moralia (lib. xxxiv, cap.19):"The Saints do not pray for the unbelieving and impious that are dead, because they shrink from the merit of their prayer, concerning those whom they already know to be condemned to eternal punishment, being made void before that countenances of the just Judge."  This is curiously inconsistent with the popular legend, first heard in the eight century, that St Gregory, moved by the tale of the Justice and humility of Trajan towards the poor widow whose son had been slain, prayed and obtained that the soul of the Emperor might return from Hell to his body to win his salvation. This inconsistency is noticed by St Thomas Aquinas, who discusses the story at some length (Summa Theologica, III Suppl Q 71, A. 5)----The Dialogues of Saint Gregory the Great Re-edited with an Introduction and Notes by Edmund G Gardner, 2010.notes, page 275

The above mentioned Moralia, Pope Gregory at length argues that Hell is unending,then concerning praying for the damned he states:

"But they say, And where then is their saintship, if they will not pray for their enemies, whom they will then see burning, though it is expressly said to them, Pray for your enemies? (Matthew 5:44) But we reply at once, They pray for their enemies at that time when they are able to convert their hearts to fruitful penitence, and save them by this very conversion. For what else must we pray for our enemies, except that which the Apostle says, That God may give them repentance, and that they may recover themselves from the snares of the devil, by whom they are held captive unto his will? (2 Timothy 2:25-26) And how will prayers be made at that time for them, when they can no longer be in any degree turned from iniquity to works of righteousness? There is, therefore, the same reason for not praying then for men condemned to eternal fire, as there is now for not praying for the devil and his angels who have been consigned to eternal punishment. And this is now the reason for holy men not praying for unbelieving and ungodly men who are dead; for they are unwilling that the merit of their prayer should be set aside, in that presence of the righteous Judge, when in behalf of those whom they know to be already consigned to eternal punishment. But if even now the just when alive do not sympathize with the unjust who are dead and condemned, (when they know that they themselves are still enduring from their flesh that which will be called into judgement,) how much more severely do they then regard the torments of the wicked, when, stripped of every sin of corruption, they will themselves cleave more closely and firmly to righteousness? For the power of severity so absorbs their minds, by means of their cleaving to the most righteous Judge, that they take no pleasure whatever in any thing which is at variance with the strictness of that inward rule.  But because we have made these brief remarks against the followers of Origen, as the opportunity occurred, let us go to the course of exposition...."--St Gregory the Dialogist (Pope Gregory the Great), Moralia, Book XXXIV, XIX, 38 (page 647)

I should also note that Pope Gregory the Great's doctrine on purgatory was that it was solely for venial (minor) sins:

"Each one will be presented to the Judge exactly as he was when he departed this life. Yet, there must be a cleansing fire before judgement, because of some minor faults that may remain to be purged away. Does not Christ, the Truth, say that if anyone blasphemes against the Holy Spirit he shall not be forgiven 'either in this world or in the world to come'(Mt. 12:32)? From this statement we learn that some sins can be forgiven in this world and some in the world to come. For, if forgiveness is refused for a particular sin, we conclude logically that it is granted for others. This must apply, as I said, to slight transgressions."--Gregory the Great[regn. A.D. 590-604], Dialogues, 4:39 (A.D. 594),in FC,39:248

Concerning the eternal nature of damnation, he denounces those that say damnation and punishment ends as making Christ a liar by issuing false threats, which makes it reasonable His promise of rewards are also lies:

"For there are those even now, who neglect to put an end to their sins, for the very reason that they suspect that the future judgements upon them will, some time or another, have an end. To whom we briefly reply, If the punishments of the reprobate will at any time be ended, the joys of the blessed will also be ended at last. For the Truth says by His own mouth, These shall go away into eternal punishment, but the righteous into life eternal. (Matthew 25:45) If, therefore, this is not true which He has threatened, neither is that true which is promised. But they say, He threatened eternal punishment to sinners, in order to restrain them from the perpetration of sins; because He ought to threaten, not inflict, eternal punishments on His creature. To whom we reply at once: If He has made false threats in order to withdraw from unrighteousness, He has also made false promises, in order to encourage to righteousness. And who can tolerate this madness of theirs, who, while they assert in their hair offers that they punishments of the reprobate are terminated, overthrow by their assertion the rewards, and recompenses, of the Elect also? Who can tolerate their madness, who endeavor to establish that that is not true which the Truth has threatened concerning eternal fire, and who, while busy in declaring God to be merciful, are not ashamed to proclaim Him to be false?

But they said, A fault, which has an end, ought not to be punished without end. Almighty God is doubtless just, and that which is not committed with eternal sin, ought not to be punished with eternal torment. To whom we reply at once, that they would say rightly, if the just and strict Judge at His coming considered not the hearts, but only the doings of men. For the wicked have sinned with a limit, because their life had a limit. For they would have wished to live without end, in order that they might continue in their sins without end. For they are more eager to sin than to live; and they therefore wish to live for ever here, in order that they may never cease to sin, as long as they live. It pertains then to the justice of the strict Judge, that they should never be free from punishment, whose mind desired when in this life never to be free from sin; and that no end of punishment should be granted to the wicked, because as long as he was able he wished to have no end to his sin....."--St Gregory the Dialogist (Pope Gregory the Great), Moralia, Book XXXIV: XIX, 38 (page 644)

Secondly, it must be noted that in none of St Gregory's extant writings does he ever mention this miraculous event. Why would he omit such a great work of God, if this in fact happened? Painstaking work efforts have been taken to preserve this writing!

Thirdly, this story appears to have been invented by an anonymous Whitby (England) monk. The version of the story found on Eastern Orthodox websites citing St John of Damascus is actually a pseudopigraphical writing from the 9th to 10th century called now Pseudo-Damascene. This era has a lot of forgeries, this was the same era that the False Decretals were written including the famous "Donation of Constantine." 

"The Unbounded Community: Papers in Christian Ecumenism in Honor of Jaroslav Pelikan" deals at length with the Gregory-Trajan legend and its dubious sources. 

"In the next chapter of the Gregory-Trajan legend we move to the Greek church, to a work erroneously ascribed to the eighth-century theologian John of Damascus but which must date to the late ninth or early tenth century because of it makes use of the vitae Gregorii of both John the Deacon and Pseudo-Paul. The author clearly prefer Pseudo-Paul's version. The text is a sermon encouraging prayer for the dead. Pseudo-Damascene brings forward Thecla and Trajan to make the same points. In each case, the person prayed into heaven was a pagan. Second, God will hear the prayers of ordinary Christians not just those of great saints. And third, the efficacy of the prayers of Thecla and Gregory for their respective pagans is not to be doubted. Given John the Deacon's challenge to the credibility of the Trajan legend, Pseudo-Damascene takes pains to stress its appearance by everyone in the east and west alike. With respect to Trajan, he emphasizes the emperor's virtue; incorrect belief was the only blot on his record. Still, since such pagans can be prayed out of hell and into heaven, how much the more can Christians who have died in the faith be helped by the prayers of their co-religionists. In addition, in opposition to people who say that few were saved in Christ's harrowing of hell, Pseudo-Damascene thinks that the reverse was the case. Many were saved thereby, he asserts, so as long as they lived upright lives...…"--The Unbounded Community: Papers in Christian Ecumenism in Honor of Jaroslav Pelikan The Virtuous Pagan, Page 49

 and, noting the effects of Pseudo-Damascene in Eastern theology:

"...the confusion between this author and the John of Damascus revered as an authority in the Greek church helps to explain what happened next, the institutionalization of prayers for the dead, including the damned, by the Greek church and its Slavic daughter churches. By the thirteenth century, these churches had set aside the third Saturday before Lent for prayer for the dead of all sorts, in a formal liturgy whose perdurance can be documented until the sixteenth century. Aside from this influence on the liturgy, Pseudo-Damascene also had a marked influence on the eschatology of the eastern churches. From the eleventh century onward, the belief that the prayers of living Christians could save pagans who were damned, or mitigate their sufferings, received support from eastern theologians; and Trajan was even enrolled in their calendar of saints. These developments are related to the fact that the doctrine of purgatory was not taught in the eastern churches. That fact, paradoxical in the light of the Latin ancestry of the Gregory-Trajan legend, in turn became a stumbling block impeding the hoped-for reunion of the Greek and Romans churches at the Council of Ferrara-Florence in 1438-39."--The Unbounded Community: Papers in Christian Ecumenism in Honor of Jaroslav Pelikan The Virtuous Pagan, Page 50

The book also notes the effects in the West, many believed virtuous pagans were saved, a few believed some would eventually be saved, however, unlike the East--the West did not develop prayers for the damned, but rather dogmatized further that those who die in original sin alone or moral sin will be in Hell forever. The only effect in the West is it asked the question of the moral people who live a good life but die without baptism.  Even before this at least in the case of catechumen and martyrs, was that they would be regenerate before they die and be taken in to heaven.

St Thomas Aquinas on the case of Emperor Trajan and Pope Gregory the Great denies it proves prayers for the damned will benefit them:

Reply to Objection 5. Concerning the incident of Trajan it may be supposed with probability that he was recalled to life at the prayers of Blessed Gregory, and thus obtained the grace whereby he received the pardon of his sins and in consequence was freed from punishment. The same applies to all those who were miraculously raised from the dead, many of whom were evidently idolaters and damned. For we must needs say likewise of all such persons that they were consigned to hell, not finally, but as was actually due to their own merits according to justice: and that according to higher causes, in view of which it was foreseen that they would be recalled to life, they were to be disposed of otherwise.

Or we may say with some that Trajan's soul was not simply freed from the debt of eternal punishment, but that his punishment was suspended for a time, that is, until the judgment day. Nor does it follow that this is the general result of suffrages, because things happen differently in accordance with the general law from that which is permitted in particular cases and by privilege. Even so the bounds of human affairs differ from those of the miracles of the Divine power as Augustine says (De Cura pro Mort. xvi). --St Thomas Aquinas, Summa Theologica, III Suppl Q 71, A. 5

In addition, I should note that praying for the damned was generally in the West condemned, rejected or discouraged in part because the West generally saw mortal sin and original sin as things one cannot repent of after death, therefore Hell is not escapable. One of the great Eastern theologians, St John of Damascus, who is at times cited in the debate over praying for the damned (see Pseudo-Damascene, "Homily for Meat-Fare Saturday" above), stated neither angels nor humans can repent after a certain point:

All wickedness, then, and all impure passions are the work of their mind. But while the liberty to attack man has been granted to them, they have not the strength to over-master any one: for we have it in our power to receive or not to receive the attack. Wherefore there has been prepared for the devil and his demons, and those who follow him, fire unquenchable and everlasting punishment (Matthew 25:41). 

Note, further, that what in the case of man is death is a fall in the case of angels. For after the fall there is no possibility of repentance for them, just as after death there is for men no repentance.--St John of Damascus, PG 94,877. An Exposition of the Orthodox Faith (Book II), Chapter II

If St John Damascene believed there will be no repentance after death, how can the wicked be rehabilitated? If Hell makes them just, apart from repentance, won't that just man be repentant for this wickedness that landed him in Hell in the first place?

Being revised and to be continued....