Abū Ḥafṣ likewise transmitted through his chain of transmission from ʿAmr ibn Shuʿayb, from his father, from his grandfather, that the Messenger of Allah (peace and blessings be upon him) said: “Whoever practices medicine without previously being known to practice medicine is liable.”

The second category comprises those whose conduct is assessed with respect to trustworthiness and dishonesty, such as goldsmiths, weavers, fullers, and dyers, since they may abscond with people’s property. The official should therefore investigate which of them are trustworthy and honest, allow them to continue their work, remove anyone whose dishonesty becomes apparent, and publicize his misconduct so that those unfamiliar with him are not deceived by him. It has also been said that the guards and officials responsible for public security have a greater claim to investigate the conduct of such people than the officials responsible for ḥisbah, since dishonesty is connected with theft.

As for those whose work is assessed according to its quality or deficiency, this is a matter reserved exclusively for the officials responsible for ḥisbah. They may generally denounce the defective and poor quality of their work, even when no one has brought a complaint concerning it. However, when it concerns a particular piece of work in which a craftsman has made a habit of corruption and deception, and the aggrieved party seeks redress against him, the official should confront him with censure and reprimand. If this entails financial liability, the nature of that liability must be considered. If determining it requires estimation or valuation, the muḥtasib may not adjudicate it, since this requires independent legal reasoning in a judicial capacity. The judge is therefore more entitled to examine the matter, order payment of compensation, and impose disciplinary measures, because this ensures equitable treatment and deters transgression.

It is not permissible to fix the prices of staple foods, or of anything else, whether in times of low prices or high prices. As for the matters that he may denounce among the rights shared between the rights of Allah Most High and the rights of human beings, these include preventing people from looking over into one another’s homes. A person whose building rises above his neighbor’s is required to screen his rooftop. In the report of Ibn Manṣūr, he said concerning a man who looks over his neighbor: “The screen is incumbent upon the one who overlooks.”