The Sharī'ah is divided into two parts: external and internal. The department of Sharī'ah relating to external deeds like salāh and zakāh is called 'fiqh', while the one dealing with internal feelings and states of the heart is called 'tasawwuf'. Both are commands in the Qur'ān. Thus, while commanding salāh and zakāh, the Qur'ān also commands gratefulness and love of Allāh ta'ālā, and condemns the evil of pride and vanity.
Similarly, in the books of hadīth, along with the chapters on 'ibādāt, trade and commerce, and marriage and divorce, are to be found the chapters on riyā (showing off), takabbur, hasad, sabr, shukr etc. These commands are as much a mandatory requirement as the ones dealing with external deeds.
On reflection, it will be realised that all the external deeds are designed for the reformation of the heart. That is the basis of success in the hereafter, while the despoiling of the heart is the cause of total destruction. This is precisely what is known in technical terms as tasawwuf. Its focus is tahzīb-al-akhlāq (the adornment of character); its motive is the attainment of Divine Pleasure; its method is total obedience to the commands of the Sharī'ah.
Tasawwuf is the soul of Islām. Its function is to purify the heart from the lowly, bestial attributes of lust, evils of the tongue, anger, malice, jealousy, love of the world, love of fame, niggardliness, greed, ostentation, vanity, deception etc. At the same time, it aims to adorn the heart with the lofty attributes of repentance, perseverance, gratefulness, fear of Allāh ta'ālā, hope, abstinence, tawhīd, trust, love, sincerity, truth, contemplation etc.
To diagnose and treat the diseases of the heart normally requires the help of an expert mentor or shaykh. Here are the qualities of a good shaykh:
- He possesses necessary religious knowledge.
- His beliefs, habits and practices are in accordance with the Sharī'ah.
- He does not harbour greed for worldly wealth.
- He has himself spent time learning from a good shaykh.
- The scholars and good mashā'ikh of his time hold a good opinion about him.
- His admirers are mostly from among the people who have good understanding of the religion.
- Most of his followers follow the Sharī'ah and are not seekers after this world.
- He sincerely tries to educate and morally train his followers. If he sees anything wrong in them, he corrects it.
- In his company, one can feel a decrease in the love of the world and an increase in the love for Allāh ta'ālā.
- He himself regularly performs dhikr and spiritual exercises.
In searching for a shaykh, do not look for his ability to perform miracles (karāmāt) or to foretell the future. A very good shaykh may not be able to show any miracles. On the other hand, a person showing supernatural feats does not have to be a pious person, or even a Muslim. The prominent Shaykh Bayazid Bustami says: 'Do not be deceived if you see a performer of supernatural feats flying in the air. Measure him on the standards of the Sharī'ah.'
When you find the right shaykh, and you are satisfied with his ability to provide spiritual guidance, you perform bay'ah or pledge. This is a two-way commitment; the shaykh pledges to guide you in the light of Sharī'ah and you pledge to follow him.