Hamdun Kassar is the greatest representative of the Malāmatiyya school, which emerged in Khurasan in the 9th century. (Since the subject of the Malāmatiyya will be addressed later, here it will suffice to point out some of his ideas.)
Kassar, the master of the malāmīs who did not attach importance to outward form and ostentation, received spiritual inspiration from Abū Turāb an-Naḫshabī. Naḫshabī says: "Whoever wears the dervish cloak is begging, and whoever sits in the lodge is begging."
Hamdun, whom ʿAṭṭār introduced as the "sign of malāma" (nişane-i meliimet), was also a prominent figure in the science of fiqh (Islamic jurisprudence) in his time. The subjects he particularly emphasized were humility, not being led by the desires of the nafs (the lower self), and not disclosing the secrets of the inner world to others. Another issue to which the malāmīs of this period attached importance was to be engaged in social life and to have an occupation, rather than gathering in a specific place called a lodge (dergāh). According to Kassar, who said, "What destroys friendship among people is love of the world," it is far superior for a person to be known as a barber or similar profession than to be known as a dervish or ʿārif (gnostic). This attitude would later lead all malāmīs to necessarily enter a profession and contribute to production.
Malāmati thought would show great development in the 15th century with the Bayramī malāmīs.