Sufism or dervishism is a method based on the rules of conduct, to purify the soul and abandon the world to reach God and the perfection of the soul. The literal meaning of Sufism is to wear wool, and the name Sufis was chosen because of their woolen clothing, which is a sign of asceticism.

Sufism is more associated with the rules of abandoning the world and asceticism; while mysticism is a comprehensive and absolute school of spiritual conduct that includes Sufism and in some cases has considered mysticism superior to "individual" conduct.

Various opinions have been expressed in the definition of Sufism, but its foundations are based on a way to know the Creator of the world, discover the truths of creation, and establish the connection of the perfect human being with humanity and truth through a mystical and esoteric path and conduct, not through rational reasoning. Its subject is the negation of self-centeredness and annihilation and joining the Creator of existence. The method of Sufism is to enter various valleys, including stages of advancement from the stage (valley) of seeking to higher stages or the seven valleys of Attar to master the soul and abandon worldly interests and self-control.

Islamic mysticism has a wide scope and is mixed with the path of Sufism, and in some cases there is an identical or mixed understanding of the two. From a linguistic point of view, the two are sometimes used interchangeably, because the truth of Islamic mysticism is Sufism, general and scientific-terminological matters can be placed under the title of Islamic mysticism, and the famous path in Islam is often brought under the title of "Sufism". Some authors, such as Murtaza Motahari, have also presented two types of understanding of these two concepts, and consider mysticism to be the scientific aspect and Sufism to be its social and obvious dimension.

Sheikh Hurr Ameli believes:

The Imamiyya Shia and all the Twelver sects from the time of the Prophet of Islam - may God bless him and grant him peace - have agreed on the invalidity of Sufism and the negation of Sufism, and the Shia of the Ahl al-Bayt have always sought to deny Sufism, following their infallible Imams.

He also believes: All Shiites have denied the Sufi sects and have quoted many hadiths from their Imams condemning them, and Shiite scholars have written many books rejecting this sect and proving their kufr.