What Is Sufism ?

1. The reality of tasawwuf which is defined by truthful self-orientation (sidq al-tawajjuh) to Allah Most High.
2. The pivot of truthful tawajjuh is to single out the heart and the body for [obedience of] Allah Alone.
   
3. Tasawwuf in relation to Dîn is like the soul in relation to the body.
4. The Sufi examines the factors of perfection and deficiency.
5. The Jurist examines whatever discharges liability (mâ yusqitu al-haraj) while the scholar of juridical/doctrinal Principles (al-usûlî) examines whatever makes one's faith valid and firmly established. Therefore the Sufi's perspective is more specific than both of theirs, consequently their criticism of him is valid, while his criticism of either of them is invalid. Hence 'the Sufi among Jurists is better than the Jurist among Sufis.'
6. To display the nobility of tasawwuf, its evidence being both by demonstration and by textual precedent (burhânan wa nassan).
7. Fiqh [jurisprudence] is the precondition for the validity of tasawwuf and that is why it has precedence over it.
8. Terminology and its specific applicability to each discipline exclusively of others.
9. The keys of spiritual opening concerning which there are four rulings: first principles; truthful aspiration towards attainment; longing for spiritual realities; and quitting the guideline of what is transmitted (al-manqûl) once one obtains self-realization (al-tahqîq).
10. It is a wonderful and strange path built on the permanent following of what is better and best: in doctrines it consists in following the Salaf; in rulings, fiqh; in meritorious deeds (al-fada'il), the scholars of hadith; and in high manners (al-âdâb), all that is conducive to the wholeness of hearts."

Some definitions of tasawwuf:
Tasawwuf: Purification of the self from all that is other than the remembrance and obedience of Allah; the realization of ihsân (excellence); zuhd (asceticism) combined with ma rifa (knowledge of Allah); the attribute of the Sufi. "Ceasing objection" (al-Su luki); "Abandoning the world and its people" (Ibn Sam un). "Tasawwuf is neither knowledge nor deeds but an attribute with which the essence of the Sufi adorns itself, possessing knowledge and deeds, and consisting in the balance in which these two are weighed." (Ibn Khafif)

Some definitions of the Sufi:
Sûfî, pl. Sûfiyya: One who follows the path of tasawwuf, "He who gazes at the Real in proportion to the state in which He maintains him" (Bundar). They wore wool (sûf): "I found the redress of my heart between Makka and Madina with a group of strangers people of wool and cloaks" (ashâb sûf wa abâ'). Sufyan al-Thawri as cited from Khalaf ibn Tamim by al-Dhahabi, Siyar A lam al-Nubala' (Dar al-Fikr ed. 7:203).