”I have chosen four things to know, and have discarded all the knowledge in the world besides.”
”One,” he answered, "is this: I know that my daily bread is apportioned to me, and will neither be increased nor diminished; consequently I have ceased to seek to augment it.
Secondly, I know that I owe to God a debt which no other person can pay instead of me; therefore I am occupied with paying it.
Thirdly, I know that there is one pursuing me (i.e. Death) from whom I cannot escape; accordingly, I have prepared myself to meet him.
Fourthly, I know that God is observing me; therefore I am ashamed to do what I ought not.”
— [The "Kashf al-Maḥjūb, "the Oldest Persian Treatise on Sufism by Shaykh 'Ali b. Hujwīrī/Dātā Ganj Bakhsh]