What is the ruling on dealing with checks in buying and selling, and is it permissible to sell a present commodity for deferred checks with an increase in price, or to sell a deferred commodity for deferred checks without an increase? And is it better for the seller to collect the check from the bank, or for the buyer to hand over the money directly? And is it permissible to reduce the price in exchange for reducing the number of installments?

The basic ruling is that dealing with checks is permissible because it is a legitimate form of debt documentation. It is permissible to give the seller a check in exchange for goods received immediately, or post-dated checks in exchange for goods received immediately, even if the deferred price is higher than the current price.

An exception to this is what requires immediate possession, such as gold and silver. It is not permissible to deal in them with uncertified checks. As for giving post-dated checks in exchange for goods received at a later date, it is permissible if the sale is for a described, absent specific item. However, it is not permissible if it is a salam (forward) sale, in which case the price must be paid immediately.

There is no problem with the seller cashing the check from the buyer's account if there are sufficient funds, because it is a legitimate transfer. However, if there are no sufficient funds, it is not permissible to hand over the check without informing the seller that the check is only for documenting his right; otherwise, it would be considered deception.

It is not permissible to accelerate some installments in exchange for a reduction in part of the price, as this is a form of usury known as "give and take quickly."