Bulgakov goes all in in the final chapter of his theological trilogy On Divine Humanity, specifically chapter 8 of The Bride of the Lamb, published posthumously in 1945.
Bulgakov, Sergius (1871-1944), leading Russian Orthodox systematic theologian of the 20th century, dean and professor of dogmatic theology at Saint Sergius Theological Institute in Paris for 20 years until his death.
“It is a bizarre conception of the parousia to limit its power to a judgment whereby heaven and hell are separated and hell is eternalized. What virtue and justification would the parousia have if part of humanity turns out to be unprepared for it? In that case, the parousia would not attain its goal, or it would even attain the opposite: the establishment of an eternal hell. But does this justify the parousia? A separation can be accepted only if, in the final analysis, it nonetheless attains the goal of the universal salvation or the sophianization [indwelling acceptance of and free cooperation with the Holy Spirit, God being “all in all”] of creation. Otherwise, creation would appear to be an error or failure, since it would end with the eternity of hell [even in annihilation of the sinner out of existence], even if this were accompanied by the eternity of heaven. An eternal separation of humanity into the elect and the reprobate is clearly not the final meaning of creation. One must therefore suppose this separation has an inner proportionality of grace that assures a positive final sum of all the pluses and minuses of history, a universal harmony, total and beautiful. In other words, the judgment that separates the sheep from the goats and good from evil, both in humankind in its entirety and in individual hearts, is not the definitive conclusion of eschatology. It is only the first event of eschatology, the beginning, not the end. Both the judgment and the separation must be understood not as a static unchangeability but as a dynamic striving beyond their limits, on the pathways to universal deification or salvation. Only deification is capable of justifying creation. It is the only theodicy. …] This pathway can end only with the filling of the void that appeared in heaven as a consequence of the fall, [eve] with the return of the fallen angels, the ‘lost sheep’, to the fullness of the kingdom of God, where God is definitively all in all without any limitation or exception, and creation is without any failure or even minus: ‘He shall have put down all rule and all authority and power. For he must reign till he hath put all enemies under his feet.’”