The Concise Oxford Dictionary of World Religions (2357 page)

(for suggested etymologies, see
TA
AWWUF
). Muslims who seek close, direct, and personal experience of God, and who are often, therefore, described as mystics. Sufism is usually treated as a single phenomenon, although it is made up of different strands and styles. Sufism is a major part of Islam, and S
f
s have been particularly important in the spread of Islam. By the 18th/19th cent. CE, at least a half (perhaps as many as three-quarters) of the male Muslim population was attached in some sense to a S
f
ar
qa
(order). Thus although Sufism has often been contrasted with the forms of Islam concerned with f
qh and
shar
‘a
(i.e. with the lawful ordering of Muslim life), and although there have historically been clashes between the two, there is no inherent or necessary conflict: S
f
s in general have been insistent on the necessity for the proper observance of Islam (examples are
al-Mu
sib