Sayyiduna Abu Huraira (may Allah be pleased with him) said: The Messenger of Allah (peace and blessings be upon him) forbade the sale of gharar (transaction involving uncertainty or deception).
Brief Explanation
(Commentary on Hadith 2589)
A deceptive sale (bay‘ al-gharar) is that in which there is uncertainty regarding its acquisition or non-acquisition, such as selling a fish while it is still in the water, or a bird while it is in the air, and conducting their purchase and sale.
Similarly, the sale of a runaway slave, the sale of what is in the womb (bay‘ al-haml), the sale of the musarrat (bay‘ al-musarrah) which has just been mentioned, and other such sales in which there is deception.
From this hadith, it is understood that any transaction or sale in which there is deception is not permissible. There are various forms of this, which will be mentioned ahead.
In the era of ignorance (Jahiliyyah), sales such as muhaqalah, muzabanah, and selling fruits before they ripen—these were all reprehensible practices in vogue, and in them there was a strong possibility of both profit and loss.
Sometimes the buyer would gain excessively, and at other times he would even lose his principal capital.
Islam prohibited such sales.
Nowadays, in place of such deceptive methods, things like lotteries, gambling, horse races, etc., have taken their place, which, in the light of Islamic rulings, are not only impermissible but also fall within the domain of usury and interest.
Severe warning has been mentioned regarding those who deceive in buying and selling. It is stated: «مَنْ غَشَّنَا فَلَيْسَ مِنَّا.» Its mention has already passed under hadith number (2577).