Narrated by Abdullah bin Abbas (may Allah be pleased with them) that the Prophet Muhammad (peace and blessings be upon him) said:“(Do not) go out to meet trading caravans (coming to the market before they arrive), do not tie up the udders of animals (to deceive the buyer about the amount of milk), and do not (pretend to be a buyer and) sell each other’s goods (by false bidding).” Imam Tirmidhi says:
1- The hadith of Ibn Abbas (may Allah be pleased with them) is Hasan Sahih,
2- In this chapter, ahadith have also been narrated from Ibn Mas’ud and Abu Hurairah (may Allah be pleased with them),
3- The people of knowledge act upon this; they do not consider it permissible to sell such an animal whose milk has been withheld in its udder,
4-“Muhallifah”refers to such an animal whose milk has been left in its udder, and its owner has not milked it for a few days so that milk collects in its udder and the buyer is deceived by it. This is a form of fraud and deception.