" Now,the very idea of this warfare is dramatically unfolded when we
come to the Fravartis of human beings. In the prelude to the
millenniums of the period of mixture, Ohrmazd offered them
the choice from which their entire destiny originates: they
could either live in the celestial world sheltered from the ravages
of Ahriman, or else descend to earth there to be incarnated
in material bodies and struggle against the counterpowers
of Ahriman in the material world. Their answer to
this proposal was the yes which gives their name its full meaning,
most significantly for our purpose: those who have chosen. In
practice the fravarti incarnated in the terrestrial world finally
became identified in religious representations purely and simply
with the soul. "

― Henry Corbin , The Man of Light in Iranian Sufism (Revised)