St Maximus the Confessor and Apokatastasis

 Online and elsewhere it's been suggested that St Maximus the Confessor professed a heretical understanding of apokatastasis, that is universal reconciliation. The doctrine that Hell is essentially a purgatory, which fires will eventually burn out and the sinners will be taken to heaven. It would be problematic if St Maximus did profess universalism since it was condemned in AD 543 by the Pope, Patriarch of Constantinople, and Emperor.

One quote floating around online attributed to St Maximus (typically in Orthodox forums) is:

"We should pray that apokatastasis is true, but it would be foolish to preach it as doctrine"

The source is rarely, if ever, cited. The implication is that the doctrine should be hoped for but certainly not preached and be kept secret. This is the contention by people like Hans Ur von Balthasar who believed St Maximus secretly held the doctrine but did not want to come out and say it to avoid suspicion of heresy and the implication it might bring.

 One Eastern Orthodox priest informed me the source is "Expositions on Psalm 59" from Migne, Patrologia Graeca. A translation of Expositions on Psalm 59 is available online by Paul Blowers (a Protestant). No where in it is the word apokatastasis used, or is the doctrine hinted at. Its another dead end. St Maximus did have much to say on the issue. He was not utterly opposed to the term since Scripture does use it ie. Acts 3:21. I am not able to find the Greek text (Corpus Christianorum Series Graeca 23: 3-22) for this section since it's not online, however JP Migne does have it in Greek and in Latin here starting at 855.

Elsewhere, St Maximus does provide 3 orthodox understandings of the word--none of which result in universal reconciliation of the damned humans and devils. 

Ἐπειδή Γρηγόριος ὁ Νύσσης ἐν τοῖς ἑαυτοῦ συγγράμμασι, φαίνεται τοῖς μή τό βάθος ἐπισταμένοις τῆς ὑψηλῆς αὐτοῦ θεωρίας πανταχοῦ [R. πολλαχοῦ] ἀποκατάστασιν ὑπεμφαίνειν, παρακαλῶ ὅπερ ἐπίστασαι περί τούτου εἰπέ.  

Ἀπόκρισις.                    

Τρεῖς ἀποκαταστάσεις οἶδεν ἡ Ἐκκλησία. Μίαν μέν, τήν ἑκάστου κατά τόν τῆς ἀρετῆς λόγον· ἐν ᾗ ἀποκαθίσταται, τόν ἐπ᾿ αὐτῷ λόγον τῆς ἀρετῆς ἐκπληρώσας. Δευτέραν δέ, τήν τῆς ὅλης φύσεως ἐν τῇ ἀναστάσει. Τήν εἰς ἀφθαρσίαν καί ἀθανασίαν ἀποκατάστασιν. Τρίτην δέ, ᾗ καί μάλιστα κατακέχρηται ἐν τοῖς ἑαυτοῦ λόγοις ὁ Νύσσης Γρηγόριος, ἔστιν αὕτη, ἡ τῶν ψυχικῶν δυνάμεων τῇ ἁμαρτίᾳ ὑποπεσουσῶν, εἰς ὅπερ ἐκτίσθησαν πάλιν ἀποκατάστασις. Δεῖ γάρ, ὥσπερ τήν ὅλην φύσιν ἐν τῇ ἀναστάσει τῆς σαρκός ἀφθαρσίαν χρόνῳ ἐλπιζομένῳ ἀπολαβεῖν· οὕτως καί τάς παρατραπείσας τῆς ψυχῆς δυνάμεις, τῇ παρατάσει τῶν αἰώνων ἀπολαβεῖν τάς ἐντεθείσας αὐτῆς τῆς κακίας μνήμας· καί περάσασαν τούς πάντας αἰῶνας, καί μή εὑρίσκουσαν στάσιν, εἰς τόν Θεόν ἐλθεῖν τόν μή ἔχοντα πέρας. Καί οὕτως τῇ ἐπιγνώσει, οὐ τῇ μεθέξει τῶν ἀγαθῶν, ἀπολαβεῖν τάς δυνάμεις, καί εἰς τό ἀρχαῖον ἀποκαταστῆναι, καί δειχθῆναι τόν δημιουργόν ἀναίτιον τῆς ἁμαρτίας. -- ΄Αγιος Μάξιμος ο Ομολογητής: Πεύσεις και Αποκρίσεις και Ερωτήσεις και Εκλογαί διαφόρων κεφαλαίων απορουμένων , PG 90 Questiones et Dubia 13, PG 90:796AC

The Church knoweth three apokatastases. One is the [apokatastasis] of everything according to the principle (logos) of virtue; in this apokatastasis one is restored who fulfills the principle of virtue in himself. The second is that of the whole [human nature] in the Resurrection. This is the apokatastasis to incorruption and immortality. The third, in the oft-cited words of Gregory of Nyssa, is the apokatastasis of the powers of the soul which, having lapsed into sin, are again restored to that condition in which they were created. For it is necessary that just as the entire nature of the flesh hopeth in time to be taken up again into incorruption in the apokatastasis, so also the powers of the soul, having become distorted during the course of the ages had instilled in it a memory of evil, so that at the end of ages, not finding any rest, will come unto God Who hath no limit. And thus the distorted powers of the soul will be taken up into the primeval apokatastasis, into a merely discursive knowledge of, but not into the participation in, the good things [of God], where the Creator is known yet without being the cause of [their] sin.--St Maximus, Ad Thalassium, PG 90:796BC. Cited in the Disputations with Pyrrhus trans. by Farrell, Introduction, p. xxxii

Below is a separate translation of the blue text:

“The third meaning [of apokatastasis] is used by Gregory especially in reference to the qualities of the soul that had been corrupted by sin and then are restored to their original state. Just as all nature will regain, at the expected time, its completeness in the flesh [at the resurrection], so also will the powers of the soul, by necessity, shed all imprints of evil clinging to them; and this after aeons have elapsed, after a long time of being driven about without rest [stasis]. And so in the end they reach God, who is without limitations [peras]. Thus they are restored to their original state [apokatastēnai] through their knowledge [of God], but do not participate in [his] gifts. It also will appear that the Creator cannot be blamed for any sinfulness.” Maximus, Questiones et dubia [Questions and doubts] 13, PG 90, 796AC (translated by Hans Ur von Balthasar himself in footnote 21)

Elsewhere, in his commentary on the Lord's prayer St Maximus affirms eternal torment for sins.

Indeed there exists but one happiness, a communion of life with the Word, the loss of which is an endless punishment which goes on for all eternity. And that is why abandoning his body and whatever is the body’s he strives intensely toward that communion of life with God, thinking that the only loss – even he were master of everything on earth – would be in the failure of the deification by grace which he pursues. --St Maximus the Confessor, Commentary on the Our Father

Separately, on the topic, it's also worth noting the last Church Father, St John of Damascus said:

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 Damascene, An Exposition of the Orthodox Faith (Book II):  Chapter 4