Muslim

Hadith Commentary: Benefits and Issues:
From this hadith, it is understood that selling something which is not present in front of one is not permissible.
There are three opinions of the scholars regarding this type of sale:
(1)
The sale of an absent item is not permissible.
This is the opinion of Imam Shafi'i.
(2)
The sale of an absent item is permissible, and after seeing it, the buyer has the option to keep it or leave it.
This is the opinion of the Hanafi scholars, and this view has also been attributed to Imam Malik and Imam Shafi'i.
(3)
When the correct and accurate condition of the absent item—that is, its quality and state—has been described, then the sale is permissible, and if the item does not match the described attribute and state, then the buyer has the option to keep it or leave it.
This is the opinion of Imam Ahmad and Ishaq.
One opinion of Imam Malik and Imam Shafi'i is also this, and this opinion appears to be correct because there is no risk of uncertainty (gharar) or gambling (qimar) in it.

Hadith Commentary:
Bay‘ mulamasah is when a person says to another that when you touch my garment and I touch your garment, the sale will become binding.
In the era of ignorance (Jahiliyyah), this type of sale was commonly practiced.
Since there is deception and ignorance involved in it, the Shari‘ah has prohibited it.

Commentary:
In the blessed era of the Messenger of Allah (sallallahu alayhi wa sallam), the people of ignorance (ahl al-jahiliyyah) used to conduct deceptive transactions. The Prophet (sallallahu alayhi wa sallam) prohibited all of them. This “mulamasah” and “munabadhah” were also types of such ignorant transactions in which there was clear deception. For example: the seller would say to the buyer that whichever cloth your hand touches, it is sold to you for such-and-such price—regardless of which cloth he touched, even if it was completely torn from the inside. The sale would be finalized merely by touching it. There was no permission to open and inspect it, and later it could not be returned either. This was called “mulamasah.” Similarly, the seller would throw something (a cloth or something else) towards the buyer, and by this act alone, the transaction would be finalized. There was no permission to examine or inspect that item. Later, that item could also not be returned, no matter how defective it was. This was called “munabadhah.” It is obvious that how could the Shari‘ah permit such ambiguous transactions and deception? Therefore, they were strictly prohibited. Another explanation of “munabadhah” has also been given: the buyer would throw a pebble, and whichever item the pebble landed on, its sale would be finalized without any investigation as to what kind of item it was.

Benefits and Issues:

➊
When purchasing something, the buyer has the right to thoroughly inspect and check the item beforehand, so that he may know whether the item is good or bad, and whether it has any defects, and if so, to what extent. Based on this, he can decide whether it is appropriate to purchase it at a certain price.

➋
Any sale in which this right of the buyer is taken away is invalid and unlawful.

➌
Lotteries and such prize schemes in which it is uncertain what one will receive are all un-Islamic.