
In The Name of Allah The Beneficent The Merciful
PURPOSE
The purpose of Tasawwuf is to gain the companionship of Allah. It is gained through the pleasure of Allah and a special closeness to Him, and as a result of which the slave of Allah experiences two states: one is that of Slavery (abdyat), and the other is that of attentiveness to Allah (huzuri).
Slavery demands humility in front of Allah. Because by definition a slave doesn't have rights to anything. His efforts are only to gain the will of his Master. This slave is thankful at whatever his Lord gives to him -- for if he hadn't received it, then he would not have gotten it with his own power. For this reason he is grateful to his Master. A basic difference between a slave and a servant is essentially that a servant has some rights whereas a slave doesn't. A servant is employed for a specific chore at a specific salary for a certain time. If asked to render a different service, he can by right refuse to perform it. But a slave on the other hand must do everything according to the Master's will. There is nothing that he can claim for himself.
With Attentiveness to Allah, the heart is filled at most times with the feeling that he is seeing Allah i.e. a state of surety. Or, that Allah is watching over him. This has been stated as:

Worship Allah, Whose Power and Knowledge encompasses the entire universe. He is fully knowledgeable of the secrets hidden in the hearts. Whosever's heart attains this state, he will never dare to disobey Allah. His heart will forever be aware of Allah's presence. It will lead him to the love and attraction of obedience, and will produce disgust and repulsion to disobedience. And due to this, it will be easy for him to leave every wrong for the pleasure of Allah The Pure. And His obedience for His Own Pleasure will be easy for him.