@branman65 @BowsacNoodle @whiteman_ It's the robes of the Great Schema, the highest order of monasticism within Orthodoxy. I believe there are only ever a few monks in the order at any given time.

"The ultimate goal of a Monk is the Order of the Great Schema (or Angelic Habit). One who aspired to that dignity usually struggled for many years in the monastic life and often it was not conferred until the end of a Monk's life. Those who reached that state usually spent the rest of their lives in complete seclusion and silence within the Monastery or a specially-prepared Skete or Hermitage, where laymen could not enter even to pray."