On the whole, I would regard Father Seraphim Rose, the American born Russian Orthodox monk (later 'Hieromonk' or Priest--monk) as the Western man of the Twentieth Century most advanced in holiness (theosis) of whom I know.
But the way in which I understand this fact has changed since first I became aware of him and absolutley immersed myself in his work somewhat more than three years ago.
Fr Seraphim died in 1982, and at first I assumed that his life marked the beginning of an Orthodox revival in the West, with Fr Seraphim as a bridge between Holy Russia and the modern world - most specifically by his discipleship to St John Maximovitch
But, as I discovered more about his legacy and the events following the death of Fr Seraphim, my perspective changed, and he seemed more like the final fruition of Holy Russia, its rounding-out; than a bridge into modernity.
In particular, modern Orthodoxy does not seem to have solved the dichotomy about which Fr Seraphim wrote so much: as he describes it this dichotomy is between, on the one hand, apostasy and accommodation to the prevailing society (mostly Leftism-Liberalism, although in modern Russia there are also anti-liberal currents); and on the other hand the distortion of 'ultra-correctness' in which strict adherence to liturgical and devotional forms combines with a cold hearted and uncharitable disposition which negates the value of these practices.
Fr Seraphim was quite clear that after the death of St John Maximovitch, there were then no true Spiritual Fathers (Holy Elders, startsi) in the United States nor indeed anywhere else, and this meant that the chain of discipleship stretching back to the life of Christ was now broken, extinct.
The cause of this was, seemingly, the Russian Revolution, the Martyrdom of Tsar Nicholas and the systematic destruction by the Bolsheviks of Holy Russia and its monastic traditions.
But whatever its cause, the effect was drastically to reduce the possible degree of theosis or sanctity in the modern world, since without the supervision of a Holy Elder and the ascetic disciplines of monasticism, the higher degrees of theosis were impossible.
Hence there are now no Saints, and nobody with the authority to resolve misunderstandings and disagreements, to interpret scripture, to guide the Church etc.
So, by Fr Seraphim Rose's own account, and the accounts of those he regarded as authoritative, Orthodoxy is now and irreversibly a much diminished thing; and - I infer - does not any longer stand with its peak above all other Christian denominations, but is simply one of a group of valid denominations with its own particular strengths and weaknesses.
Yet, by his work of translation and interpretations, and by the example of his life, Fr Seraphim Rose has made it possible for us to appreciate what has been lost from the world.