That aside, the critical question is: what did the Council intend to condemn? Universalism per se or a specific kind of universalism? So what exactly did the Fifth Council condemn?
1. All forms of universalism? It seems that many thought that this was so. The fact that a lot of medieval theologians were very cautious about any affirmations of universal salvation suggests that the general opinion was that the Church had condemned universalism.
2. The proposal that one can assert all will definitely be saved? Balthasar, in his works on universal salvation, insists that all that the Council rejected was the notion that we can assert universal salvation with absolutely certainty. He argued, as do many modern theologians, that one can certainly hope all will be saved but that certainty is not permitted in light of the anathemas.
3. A version of universalism that taught a universal return of pre-existence souls to an original state. This was arguably Origen’s view but its exclusion does not rule out different versions of apokatastasis.
In defense of view 3 let me make the following observations:
First, it is clear that when apokatastasis is condemned in the fifteen canons it is always done so in association with other, problematic, ideas. Thus in anathemas I and XV the concern is with apokatastasis as linked with the idea of the pre-existence of souls and an eschatology which sees a simple return of souls to an original unity. In anathema XIV it is apokatastasis as associated with an immaterial, pantheistic eschatology. But this is not a condemnation of universalism as such. Rather, it is a condemnation of universalism as linked into a wider, theologically problematic, system of thought. Even Justinian’s anathema IX—an anathema the status of which is ambiguous given that it was not a product of the Ecumenical Council—which looks like a blanket condemnation of all universalism might, in context, be taken as a condemnation of Origenist-universalism. Certainly when the Fifth Ecumenical Council turned Justinian’s earlier anathemas against Origen into fifteen approved anathemas they nuanced it in that way. If Justinian intended a blanket condemnation of universalism that was not what the Council agreed to.
Second, in support of this interpretation we may note that Gregory of Nyssa was known to teach a version of universal salvation that denied the problematic notion of the pre-existence of souls. Neither Gregory nor his teachings are ever condemned. Indeed, Gregory was highly revered as an orthodox theologian—named the “Father of the Fathers” by the Seventh Ecumenical Council in 787—and remains so to this day. One contemporary Orthodox theologian wrote to me as follows:
Bulgakov points out, quite astutely I think, that Gregory of Nyssa’s version of apokatastasis, which is more developed and less ambiguous than that of Origen, has never been officially condemned. This means, I suppose, that any Orthodox theologian has, shall we say, a canonical loophole to speak of the apokatastasis a la Nyssa, not a la Origen—an apologetic move that Bulgakov makes.
According to Bulgakov, the doctrine of eternal hell does not have the status of a dogma in the East. Bulgakov wrote a very important essay, “Dogma and Doctrine”, in which he argued that strictly speaking, the Seven Ecumenical Councils have endorsed only two main doctrines—the trinity and incarnation with some corollaries, likes the status of Mary and the veneration of icons—and that most other central beliefs are to be relegated to the status of theologoumena [issues over which individual Christians may hold different personal opinions]. I must admit that I am more inclined to accept Bulgakov’s minimalism, than the dogmatic maximalism which characterizes, for example, the scholastic tradition in the West.
Third, when the Fifth Ecumenical Council condemned Origen by name in canon XI, the context suggests that Christology and not apokatastasis was the primary concern.
Finally, we might add that none of the central claims of orthodox Christianity, as embodied in the rule of faith or the Ecumenical Creeds, is incompatible with universalism. So universalism is certainly not unorthodox in the sense of being contrary to essential dogma. Indeed some universalists have embraced universalism precisely because they feel that it enables them to better hold together important Christian beliefs which stand in awkward tension on more traditional notions of hell (e.g., divine love for creation and divine providence over creation).