One user, a girl named Noor studying at NYU, turns him onto Sufism and Arabic poetry.
Sufism or Persian mysticism began in asceticism and ended in pantheism.
Sufism, in some form or another, could not possibly be confined to Asia.
Also, it could be said that originally Sufism owed its principles to the Alexandrian school.
Had there not been in the heart of Islamism a strong germ of esoteric teaching, Sufism could never have sprung from it.
This being the state of his mind it is not surprising that he drifted into Sufism.
Perhaps I can do no better than to quote one of the foremost authorities on Sufism in regard to Omar's teachings.
As regards religion, Burton had in early life, as we have seen, leaned to Sufism; and this faith influenced him to the end.
A study of Sufism will reveal the real Omar—hitherto but little known, if known at all.
Being asked to define Sufism, he said, "Sufism consists in giving up repose, and accepting suffering."