Although there is no evidence that the word “Tasawwuf” (the Arabic word for “Sufism”) was used by the Prophet (peace be upon him), he certainly used the word ‘Ihsan’ or spiritual sincerity. Sufi Shaykhs have said that Sufism itself is nothing other than this sincerity, or the perfect following of the way of Muhammad, both inner and outer.
Therefore, Tasawwuf, or Sufism, can in no way be divorced from the teachings of the Prophet Muhammad (peace be upon him). Anyone who acts contrary to the principles of Islam cannot be considered a Sufi, in spite of their claims. Care must be taken when choosing a guide, for as Hasan al-Basri, a Shaykh of the the 7th century said, “Association with the wicked produces suspicion of the good”.
Some commentators maintain that Sufism was an “innovation” and that it was created after the time of the Prophet Muhahammad (pbuh). However, others understand that, although the word “tasawwuf” was not in common use during the time of the prophet (pbuh), neither were words like “fiqh” (jurisprudence) or kalam (philosophy), it is clear that all of the reality of all these existed at that time, even if the names did not.