And its importance is too great to be fully encompassed; those in authority must therefore give it greater attention than any other duty. For this reason, the Commander of the Faithful, ʿUmar ibn al-Khattāb, may Allah be pleased with him, used to write to his officials:

“The most important of your duties in my eyes is prayer. Whoever upholds it and observes it faithfully safeguards his religion; whoever neglects it will neglect other duties even more.”

This was narrated by Mālik and others.

The muhtasib must enjoin Friday and congregational prayers, truthfulness in speech, and the faithful discharge of trusts. He must forbid wrongdoing, including lying, betrayal of trust, and everything these encompass, such as giving short measure or weight and practising deception in crafts, sales, religious affairs, and the like. Allah, Exalted is He, says:

“Woe to those who give short measure, who take their full measure when receiving from others, but give less when measuring or weighing for them.”

And He says in the account of Shuʿayb:

“Give full measure, and do not be among those who cause loss. Weigh with an even balance. Do not deprive people of what is rightfully theirs, and do not spread corruption in the land.”

And He, Exalted is He, says:

“Indeed, Allah does not love anyone who is treacherous and sinful.”

And He says:

“And Allah does not bring the schemes of the treacherous to success.”

In the two Sahīh collections, Hakīm ibn Hizām reported that the Messenger of Allah, may Allah bless him and grant him peace, said:

“The buyer and seller have the option of withdrawing from the sale so long as they have not parted. If they are truthful and make matters clear, their transaction will be blessed; but if they conceal facts and lie, the blessing of their transaction will be erased.”

In Sahīh Muslim, Abū Hurayrah reported:

“The Messenger of Allah, may Allah bless him and grant him peace, came upon a heap of food and put his hand into it